Service Assessment

U.S. Department of Commerce

National Oceanic and Atmospheric Administration

National Weather Service

Silver Spring, MD

April 1997

NAT OI NAL OCEANIC AND ATMOSPHERIC ADMINISTRAT OI N

U.S. DEPARTMENT OF COMMERCE

July 5 –14, 1996
Cover photograph: Hurricane Bertha - http://www.ncdc.noaa.gov/pub/data/images/.
Service Assessment

HURRICANE 

BERTHA

July 5 - 14, 1996

U.S. Department of Commerce

National Oceanic and Atmospheric Administration

National Weather Service

Silver Spring, MD

April 1997

iii

Table of Contents

Page

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii

Acronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi

Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix

Summary of Findings and Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xii

Chapter 1 Service Assessment Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Chapter 2 National Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

National Hurricane Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Hydrometeorological Prediction Center . . . . . . . . . . . . . . . . . . . . . . . . 11

Marine Prediction Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Storm Prediction Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Chapter 3 Regional Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Southern Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Eastern Region . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Appendices

Appendix A Saffir-Simpson Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

Appendix B Meteorological Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1

Appendix C Fujita Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1

Appendix D Tornado Watch Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D-1

Appendix E Aerial Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E-1
iv

Acronyms

AFOS Automation of Field Operations and Services

AOC Aircraft Operations Center

ASOS Automated Surface Observing System

AST Atlantic Standard Time

AVN Aviation Model

CWA County Warning Area

DEMA Delaware Emergency Management Agency

ECMWF European Center for Medium Range Weather Forecasting

EDT Eastern Daylight Time

EMC Emergency Management Center

EMWIN Emergency Managers Weather Information Network

ERH Eastern Region Headquarters

ET Electronics Technician

Eta Eta Model

FAA Federal Aviation Administration

FEMA Federal Emergency Management Agency

ft feet

GFDL Geophysical Fluids Dynamical Lab Model

GOES Geostationary Operational Environmental Satellite

HLS Hurricane Local Statement

HLT Hurricane Liaison Team

HPC Hydrometeorological Prediction Center

in inch

IR Infrared

kts knots

MAR Modernization and Restructuring

mb millibar

MIC Meteorologist in Charge

MPC Marine Prediction Center

mph miles per hour

MRF Medium-range Forecast Model

MRFX Medium-range Forecast Experimental Model

NAWAS National Warning System

NCEP National Centers for Environmental Prediction

NEXRAD Next Generation Weather Radar

NGM Nested Grid Model

NHC National Hurricane Center

nm nautical miles
v

NOAA National Oceanic and Atmospheric Administration

NOGAPS Naval Operational Global Atmospheric Prediction System

NOW Short Term Forecast

NWR NOAA Weather Radio

NWS National Weather Service

NWSFO NEXRAD Weather Service Forecast Office

NWSO NEXRAD Weather Service Office

NWWS NOAA Weather Wire Service

OM Office of Meteorology

PUP Principal User Processor

QPF Quantitative Precipitation Forecast

RDA Radar Data Acquisition

SOO Science and Operations Officer

SPC Storm Prediction Center

SRH Southern Region Headquarters

SSMI Special Sensor Microwave Imagery

TPC Tropical Prediction Center

TWC The Weather Channel

UTC Coordinated Universal Time

VIS Visible

VITEMA Virgin Islands Territory Emergency Management Agency

WCM Warning Coordination Meteorologist

WFO Weather Forecast Office

WSH Weather Service Headquarters

WSR-88D Weather Surveillance Radar-1988 Doppler

WV Water vapor
vi

Acknowledgments

This report was produced by having those responsible for each portion of the service provided

write their own section. Each NWS field office and NWS Regional Office affected by Bertha

conducted its own survey of the services they provided. Additionally, assessments were written

by the National Centers that provided products and services related to Bertha. The Service

Assessment Team is grateful to all those that provided valuable input into this document. The

individuals primarily responsible for the Assessment are as follows: 

Service Assessment Team

Rick Watling, Products and Services Manager, Meteorological Services Division, NWS Eastern

Region Headquarters (ERH), Bohemia, New York

Gene Hafele, Warning Coordination Meteorologist (WCM), NEXRAD (Next Generation

Weather Radar) Weather Service Office (NWSO), Houston, Texas

Scott Kiser, Technical Leader, Customer Service, Office of Meteorology (OM), Weather Service

Headquarters (WSH), Silver Spring, Maryland

NWS National Centers

Robert Burpee, Director, Tropical Predication Center (TPC), Miami, Florida

Miles Lawrence, Hurricane Specialist, NHC, Miami, Florida

Mike Schichtel, Meteorologist, Hydrometeorological Prediction Center (HPC), Camp Springs,

Maryland

Dave Feit, Chief Marine Forecast Branch, Marine Prediction Center (MPC), Camp Springs,

Maryland

Fred Ostby, Chief Operational Guidance Branch, Storm Prediction Center (SPC), Kansas City,

Missouri
vii

Weather Service Headquarters

Rainer Dombrowsky, Customer Service, OM, WSH, Silver Spring, Maryland

Linda Kremkau, Technical Editor, Customer Service, OM, WSH, Silver Spring, Maryland

NWS Regions and Field Offices

Gary Woodall, WCM, Southern Region Headquarters (SRH), Fort Worth, Texas

Harvey Thurm, Synoptic Scale Meteorologist, ERH, Bohemia, New York

Brian Smith, WCM, NEXRAD Weather Service Forecast Office (NWSFO), Omaha, Nebraska

Steve Rich, Meteorologist in Charge (MIC), NWSO, Charleston, South Carolina

Jerry Harrison, WCM, NWSO, Charleston, South Carolina

Bernie Palmer, MIC, NWSFO, Columbia, South Carolina

Steve Naglic, WCM, NWSFO, Columbia, South Carolina

Richard Anthony, MIC, NWSO, Wilmington, North Carolina

Tom Matheson, WCM, NWSO, Wilmington, North Carolina

Tom Kriehn, MIC, NWSO, Morehead City, North Carolina

Dan Bartholf, WCM, NWSO, Morehead City, North Carolina

Steve Harned, MIC, NWSFO, Raleigh, North Carolina

George Lemons, WCM, NWSFO, Raleigh, North Carolina

Tony Siebers, MIC, NWSO, Wakefield, Virginia

Hugh Cobb, Science and Operations Officer (SOO), NWSO, Wakefield, Virginia

Bill Sammler, WCM, NWSO, Wakefield, Virginia
viii

Jim Travers, MIC, NWSFO, Sterling, Virginia

Gary Szatkowski, Deputy MIC, NWSFO, Sterling, Virginia

Barbara Watson, WCM, NWSFO, Sterling, Virginia

Chet Henricksen, MIC, NWSFO, Philadelphia, Pennsylvania

Joe Miketta, WCM, NWSFO, Philadelphia, Pennsylvania

Mike Wyllie, MIC, NWSFO, New York City, New York

Gary Conte, WCM, NWSFO, New York City, New York

Bob Thompson, MIC, NWSFO, Boston, Massachusetts

Dave Vallee, Service Hydrologist, NWSFO, Boston, Massachusetts

Glenn Field, WCM, NWSFO, Boston, Massachusetts

Al Wheeler, MIC, NWSFO, Portland, Maine

John Jensenius, WCM, NWSFO, Portland, Maine

Patricia Haas, Hydrologist, Mid Atlantic River Forecast Center, State College, Pennsylvania

Israel Matos, MIC, NWSFO, San Juan, Puerto Rico

Rafael Mojica, WCM, NWSFO, San Juan, Puerto Rico

Paul Hebert, MIC, NWSFO, Miami, Florida

Jim Lushine, WCM, NWSFO, Miami, Florida

Bart Hagemeyer, MIC, NWSO, Melbourne, Florida

Dennis Decker, WCM, NWSO, Melbourne, Florida

Steve Letro, MIC, NWSO, Jacksonville, Florida

Fred Johnson, WCM, NWSO, Jacksonville, Florida
ix

Executive Summary

Background

Hurricane Bertha was an early season Category 2 storm when it made landfall on the coast of

North Carolina on July 12, 1996. Twelve deaths have been directly attributed to Bertha with

United States damages estimated at $270 million. Extensive evacuations of vulnerable areas

occurred in advance of Bertha, including 250,000 in North Carolina, 80,000 in South Carolina

and 20,000 in Georgia. Revenue losses to the tourist industry approached $40 million.

Bertha closely paralleled the southeast U.S. coast at a distance from 170 to 200 miles. This

created multiple state involvement with almost all of the U.S. east coast involved with some

watch or warning. The NHC’s track forecast was very accurate with average forecast track

errors 15 percent lower than the 10-year official track averages. Where the storm came ashore in

North Carolina, watches and warnings were posted 65 hours and 47 hours before landfall,

respectively, which far exceeds the NHC stated goals of 36 and 24 hours. Nevertheless, the

coordination between NHC and emergency managers, regarding the issuances of watches and

warnings, was frustrated by efforts to reconcile the meteorology of the event with state and local

response requirements. Bertha’s anticipated turn from a northwest direction to north-northwest

as it approached the southeast coast was agonizingly slow. This put a great deal of pressure on

the elected officials and Emergency Management Centers (EMCs) of Florida, South Carolina and

North Carolina concerning what actions to take. This was also the first time the HLT had been

fully deployed at the NHC. A Service Assessment Team was dispatched to the NHC as well as

the impacted states to investigate these issues and to evaluate the HLT.

Issues

Bertha’s slow northward turn off the Florida coast caused the state of Florida to urge NHC to

issue watches when NHC felt they were unnecessary. The major concern was that if the storm

continued to move differently than forecast, sufficient response time would not be available if

watches or warnings were issued at short notice. Similarly, South Carolina expressed the need for

early release of the official forecast track before NHC had completed the internal NWS

coordination process. Several recommendations have been made in this report to help resolve

these issues.

A variety of communication/coordination issues were also revealed. NHC/state briefings were

complicated by the fact that no single communication system was used to brief state emergency

management officials, adding to the workload of the hurricane specialists and confusion between
x

state EMCs and the NHC as to what method of coordination would be employed. Similar 

coordination problems occurred between NWS field offices and local EMCs as well as between

some state and local EMC(s). Internal coordination between NWS offices posed difficulties as

not all necessary offices are connected to the Hurricane Hotline. This problem will continue to

increase as additional NWS offices spin up to full Weather Forecast Office (WFO) status. 

The amount of meteorological information received by state and local EMCs to a large extent

depended upon the resources available to each office. Even though it is not considered an

operational system, Internet received high praise while the National Oceanic and Atmospheric

Administration (NOAA) Weather Wire Service (NWWS) continues to prove too costly for some

EMCs. Additionally, NOAA Weather Radio (NWR) coverage is still lacking in some coastal

areas. Accordingly, the NWS should seek to expand implementation of the Emergency

Management Weather Information Network (EMWIN) as well as NWR.

This was the first time the HLT was used in an operational environment. This team is a joint

venture between FEMA, the NWS and state and local emergency management officials. The

concept is to supplement the NHC staff with Federal, state and local emergency management

personnel to provide information and coordination between the NHC and emergency management

decision makers. As this is a new initiative, the HLT is still evolving in response to the needs and

desires of both the partners in the HLT and their customers. Questions remain regarding the

ultimate mission, function and operations of the HLT. Additionally, a larger resource pool of

available people to staff the HLT needs to be identified, and smoother procedures for setting up

the team’s hardware need to be established.

Some data acquisition problems were also noted. The St. Croix and St. Thomas Automated

Surface Observing Systems (ASOS) were both powered down by the Federal Aviation

Administration (FAA) when the airport towers were abandoned resulting in the loss of valuable

ground truth data. Due to the remoteness of the site, the San Juan Weather Surveillance Radar1988 Doppler (WSR-88D) remote data acquisition (RDA) unit uses generator power since

commercial power is not available. The generator produces irregular frequency fluctuations

which puts the system out of service. The FAA electronics technician was able to keep the

system operational throughout the storm, and a more permanent fix was employed after the

passage of Bertha. NWSFO Miami noted that without data off the southeast Florida coast, no

wave information is available south of Melbourne. This forced the staff to estimate waves from

their wind forecasts. 

Meteorology

Bertha was an early season Cape Verde hurricane which started as a tropical depression in the

central tropical Atlantic on July 5. For 3 days, the depression moved west-northwest at 23 to

29 miles per hour (mph) and strengthened to a hurricane on July 8 as the center moved across the
xi

Leeward and Virgin Islands of the northeast Caribbean. Bertha turned northwestward on July 9. 

Maximum sustained winds reached 115 mph at 2 a.m. Eastern Daylight Time (EDT), when Bertha

was centered 138 miles north of Puerto Rico. The last hurricane to reach this strength this early

in the season was Alma in 1966. Moving northwest, the center paralleled the Bahama islands. 

The track became north-northwest on July 10 and 11 as the center moved parallel to the coast of

Florida and Georgia. With a forward speed of 17 mph, Bertha made landfall at 4 p.m. EDT on

July 12 on the coast of North Carolina, midway between Wrightsville and Topsail Beaches.

Bertha quickly dropped below hurricane strength when it moved inland over eastern North

Carolina. Highest wind gusts reported on land were 108 mph at Camp Lejeune and Jacksonville,

North Carolina. The lowest observed sea-level pressure at landfall was 977 millibars (mb) at Surf

City, North Carolina. A value of 974 mb is assumed to be the minimum landfall pressure. Bertha

then moved northeast along the U.S. east coast, producing 45 to 60 mph sustained winds over

land from northern North Carolina to New England. Bertha was declared extratropical on July 14

when the center moved from the Maine coast to New Brunswick, Canada. 

Coastal storm surge flood heights, from Florida through New England, ranged from 1 to 4 feet,

but values to 5 feet were estimated on the North Carolina coast from Cape Fear to Cape Lookout. 

A storm surge of 6 feet was indicated near Swansboro, North Carolina.

Rainfall associated with Bertha occurred from the eastern Carolinas to Maine with many locations

receiving 2- to 4-inch amounts. Isolated reports of over 6 inches were reported from North

Carolina to Massachusetts. The maximum was 7.20 inches at Billerica, Massachusetts. Bertha’s

rapid motion through the Northeast served to limit rainfall duration and amounts.

Six tornadoes have been confirmed with four in Virginia, one in North Carolina and one in

Maryland. 
xii

Summary of 

Findings and Recommendations

National Implementation

Finding 1a: Some confusion remains as to the purpose of the HLT.

Finding 1b: The workload for the hurricane specialists, with the HLT in place, was

not reduced and in some instances increased.

Recommendation 1: In conjunction with FEMA, the functions and operations of the HLT

must be reviewed and refined. The results should be briefed at the

National Hurricane Conference and other suitable forums. FEMA

representatives are encouraged to take an active role in the

Interdepartmental Hurricane Conferences.

Finding 2: There are insufficient HLT members to support speciality functions

(electronics, communications) to avoid burnout, turnover and absences

due to sickness, annual leave, etc.

Recommendation 2: As part of the NWS/FEMA review, the specific tasks of the HLT

members must be outlined and an adequate resource pool identified. The

NOAA/NWS Hurricane Conference should be the forum for discussing

and validating HLT mission, membership and other requirements.

Finding 3: Hardware required to support the HLT is extensive and requires

significant time and effort to set up.

Recommendation 3: FEMA must provide a complete set of instructions that will assist in the

set-up process. Additionally, FEMA and NHC should identify electronic

specialist(s) who can set up and test the equipment prior to the arrival of

the HLT. Given the location of the NHC on the Florida International

University campus, NHC could explore the possibility of involving

university resources to assist in the process.

Finding 4a: There was no single communication system used to brief state emergency

management officials. This led to confusion among the EMCs.
xiii

Finding 4b: NHC was required to conduct multiple briefings when more than one

state was impacted by Hurricane Bertha. This proved to be extremely

time consuming for the hurricane specialists.

Finding 4c: During teleconferences established by the HLT, the local NWS offices

were not always involved.

Finding 4d: Several times local emergency managers were tied into state and regional

briefings coordinated through the HLT. The locals would then be

brought into a local conference call with their state and local NWS

offices. This was repetitive and not a good use of the local emergency

managers limited time.

Finding 4e: NHC briefing calls to North Carolina state emergency management

officials frequently came at times when these individuals were already in

the midst of a briefing by the NWSFO or with local emergency

management officials along the coast.

Recommendation 4: FEMA and the NWS must ensure that coordination methodologies and

protocols are firmly established before the next hurricane season. The

local NWS office(s) must be included in all NHC state conference calls to

add local expertise and to prepare for their coordination calls with local

emergency managers. 

Finding 5a: The Modernization and Restructuring (MAR) of the NWS has created a

greater need for internal forecast coordination as the number of forecast

offices has increased.

Finding 5b: As Hurricane Bertha approached the Delmarva region, confusion arose

when the wind forecasts from two NWS offices for adjacent forecast

areas were significantly different. 

Recommendation 5: The NWS needs to move quickly to establish an internal coordination

mechanism.

Finding 6: Some EMCs are having problems receiving weather information. NWR

coverage is incomplete and NWWS is too costly for some EMCs. 

Computer bulletin boards and the Internet received high praise.
xiv

Recommendation 6: The NWS should continue to seek partnerships to expand NWR

coverage in support of the Gore initiative and target resources to ensure

reliable programming and maintenance of the new systems. The NWS

must actively support implementation of EMWIN and seek additional

partnerships to ensure its availability from multiple sources. EMCs

should be reminded of other resources, such as the free redistribution of

NWWS from their state distribution point and the use of Packet Radio.

Finding 7a: A number of offices noted a truncation of some of the more lengthy

Hurricane Local Statements (HLS) on The Weather Channel (TWC). 

Moreover, it was also noted that some of the Short Term Forecasts

(NOW) were cut off at six, as opposed to eight lines. This premature

truncation of the HLS and NOW resulted in critical information not being

passed on to the viewer.

Finding 7b: The “segmented” HLS format used by NWSFO San Juan marked an

improvement over their HLSs issued during Hurricane Marilyn.

Finding 7c: NWSFO San Juan’s NOWs were informative, but some of them tended

toward the radar narrative summary style of writing.

Recommendation 7: OM needs to work with TWC to resolve the truncation issue. All offices

should be reminded of the NOW’s primary function, to serve as a

forecast of future conditions and impacts rather than a summary of past

events.

Finding 8: Potentially valuable meteorological data was lost when the St. Croix and

St. Thomas ASOS units were powered down when the FAA abandoned

their towers.

Recommendation 8: NWS and FAA officials should ensure that ASOS units remain in service

during the approach of a tropical cyclone. 
xv

Finding 9: Rip currents associated with Bertha resulted in 3 deaths and over

100 rescues along the Florida and southeast Georgia coasts. Heavy surf

advisories were canceled before two of the deaths occurred. Lack of

data off the southeast Florida coast forced forecasters to estimate wave

heights from local wind forecasts. 

Recommendation 9: NWSFO Miami must redouble their efforts at seeking partnerships with 

Beach Patrol units and other organizations to secure critical wave height 

and surf reports. 

Finding 10: Hurricane specialists were urged to change the location of watches and

warnings. This was exemplified when Bertha's slow northward turn 

resulted in Florida State officials requesting NHC to post watches on the

Florida coast when hurricane specialists felt that this was unnecessary.

Recommendation 10: NHC needs to remain sensitive to unique and special situations that 

occur which emergency managers must resolve during hurricane threats. 

State officials have the authority to issue mandatory evacuations for

vulnerable coastal areas even when NHC may feel that meteorological

conditions do not justify issuing hurricane watches or warnings. The

NWS and FEMA need to expand the present hurricane course for

emergency managers and should develop a distance learning approach to

the present NHC resident course. As a part of this course, a module

should be developed for NWS personnel at both the NHC and at local

offices to ensure that they fully appreciate emergency manager

requirements.

Finding 11: The NHC was requested to release forecast points early.

Recommendation 11: NHC should not release forecast points prior to completion of forecast 

coordination. If the meteorology changes significantly and unexpectedly

between the 6 hourly advisory forecasts, then NHC will issue a special

advisory. However, in truly unique circumstances, some coordination on

trends and changes from the previous forecast can be discussed with the

local NWSO and NWSFO so they can brief state or local EMCs prior to

the issuance of the new forecast. There is also a continuing need to

educate emergency managers and other customers about hurricane

forecasts and products and the uncertainties related to these products.
xvi

Finding 12: Hurricane strike probabilities are still not fully understood by state and

local EMCs and are being misrepresented by the media. These

probabilities are especially confusing when a hurricane is paralleling the

coast.

Recommendation 12: The NWS and FEMA should develop new educational materials related

to the use of hurricane strike probabilities as well as the use of forecasts

and forecast uncertainties in the decision-making process. This should be

included in the residence training at NHC as well as in distance learning

modules for emergency managers. These materials should also be

provided to coastal WCMs for outreach efforts to the local media. 

Similarly, NHC should investigate better ways of graphically depicting

forecasts and forecast uncertainties. 

Finding 13: Many NWS offices participate in post-storm local-level evaluations and

critiques, usually led by the WCM and/or the MIC.

Recommendation 13: This practice of local self-evaluation should be encouraged at all NWS 

offices, coastal or otherwise.

NCEP Implementation

(National Centers for Environmental Prediction)

Finding 14: The Internet has become very popular, and the information available over

the Internet from NHC received very favorable comments. Naturally,

when the hurricane was close to land, access to the NHC Homepage was

difficult.

Recommendation 14: NHC should investigate the possibility of increasing their Internet

capabilities.

Finding 15: The NHC rarely sought input from the SPC nor made attempts to ensure

that the SPC was "on the line" during the hotline coordination. As a

result, field offices that were concerned with the tornado threat were

never sure that the SPC was on the line although the SPC makes it a

practice to monitor the line continuously. 

Recommendation 15: The NHC should include the SPC in its roll call list for coordinating

advisories when a tropical cyclone threatens the U.S. mainland. In
xvii

addition, the NHC should make it a point to invite comments from the

SPC in such situations.

Regional Implementation

Finding 16a: Due to the remoteness of the location, the San Juan WSR-88D RDA

does not utilize commercial power.

Finding 16b: The RDA’s emergency generator produces an electric current with

irregular frequency fluctuations.

Recommendation 16: Officials from the SRH and Puerto Rico emergency management should

encourage the FAA to develop a plan for supplying the WSR-88D with

stable commercial power and with stable, reliable emergency generator

power.

Finding 17: The lack of reliable redissemination systems caused some delay in the

receipt of weather products necessary to the emergency management

decision-making process in Delaware. The use of the fax blast was not

always reliable.

Recommendation 17: ERH should work with FEMA Region 3 and WSH to resolve this issue.
1

Chapter 1

Service Assessment Summary

Operations of the Hurricane Liaison Team

Traditionally, local emergency managers from Florida, as well as some FEMA regional personnel,

volunteered to work at NHC to field calls from local emergency managers and to keep FEMA

national and regional offices apprised of the evolving situation from an emergency management

perspective. The 1996 hurricane season was the first real effort to formalize the ad hoc process

and make it more of a functioning unit. This resulted from the highly active 1995 hurricane

season where it became evident that something had to be done to take some of the external

pressure off of the NHC hurricane specialists. Accordingly, the HLT was formed at the request

of the State of Florida, FEMA and the NWS. The HLT was first activated during Hurricane

Bertha. Since this was the first official activation, some of its purpose and function were not

clearly understood by all of the parties involved. It was expected that the HLT could relieve some

of the external demands placed on the hurricane specialist. During Bertha, this was not the case. 

In fact, the workload was even greater due to the number of briefings that required participation

of a specialist. The HLT concept is still under development and its functions and operations are

being reviewed. A major concern is to ensure that the HLT does not detract from local

emergency managers contacts with their local NWS offices and WCMs.

Prior to the start of the 1996 hurricane season, individuals were identified and chosen who had the

necessary skills and expertise. After working Hurricane Bertha, the team realized that, given the

extended hours that are required and the possibility of a team member(s) being unavailable, a

sufficient number of skilled people were not identified to fill these positions. 

In addition to staffing, a unique set of hardware is required to meet the operational requirements

of the HLT. Since the equipment was not prepositioned and there was no dedicated electronics

expert assigned to assemble the hardware, some time was lost setting up the equipment.

The video conferencing between NHC and FEMA Headquarters ensured that FEMA senior

management and all organizations supporting the Federal Response Plan had the necessary

information to be proactive, making timely response actions. Video conferences were scheduled

twice a day for the Director of FEMA and were accomplished with minimal problems. 
2

State and Local Coordination

Florida, South Carolina, North Carolina -- Unlike FEMA Headquarters and NHC, most state

EMCs currently do not have video conference capability but expressed a willingness to add this

technology. However, due to high costs, video conferencing is not affordable to NWS field

offices. Most briefings are done via voice only with each state using differing communication

conferencing systems to speak to the NHC. Some use the National Warning System (NAWAS);

others, such as Florida, have their own conference systems with a line to NHC. Some of the

conference calls were done on NAWAS while others were made through existing Federal and

state teleconference systems but established by government operators. The South Carolina EMC

missed an NHC briefing since they were not sure whether the call was on NAWAS or some other

system.

NHC and the states agreed that a universal conferencing system needs to be established as

coordination is too difficult with multiple systems. A single system would also help decrease the

workload for the hurricane specialist as all state EMCs could be conferenced together and briefed

at once. Local NWS offices stated they were not always tied into conference calls between the

state EMCs and the NHC.

During Hurricane Bertha, many of the local EMCs were tied into HLT briefings along with their

state EMCs. After this briefing, they would then participate in another conference call, involving

EMCs in the local area, the state EMC and the local NWS. In survey team discussions with local

emergency managers, they expressed little interest in talking directly with NHC. They would

rather be tied into a telephone conference call with their surrounding EMCs and local NWS office. 

They assume the state and local NWS offices will talk with the NHC and pass information to them

during their local conference call. 

In interviewing local emergency managers, the survey team was told NWWS continues to prove

too expensive for local EMCs with limited funding. The EMWIN was discussed and could prove

to be a viable alternative for users who currently have no level of support or can afford very little. 

North Carolina officials note that the NWR is still not available in some areas along their

coastline.

The use of Internet is increasing and South Carolina and North Carolina are using the Internet as

one method to access the latest information. However, when Bertha approached the coastline,

the Internet connection to the NHC was difficult or impossible to get. 

Delaware and Maryland -- NAWAS was used as the primary communication and coordination

tool by Mt. Holly NWSFO during events of Hurricane Bertha. Delaware Emergency

Management Agency (DEMA) felt the support provided during Hurricane Bertha did not meet

the level of support provided prior to the policy change. The use of a single conference call by

several NWS offices for coordination among multiple states, as well as the loss of access to the
3

26 local municipalities on the DEMA bridge, was a major concern. Subsequent work between the

OM, ERH and DEMA has found an equitable resolution using the DEMA bridge. 

Delaware does not have an effective mechanism in place for the redistribution of both national and

local weather information and guidance. This put county and municipal emergency managers at a

disadvantage as they had no hard copies of NWS watches, warnings and statements. This forced

coordination calls to be longer as they became a dissemination mechanism rather than a

coordination tool. Delaware officials also noted several occasions where wind forecasts issued

for adjacent areas by different NWSFOs were significantly different which caused confusion and

raised the anxiety of many local emergency managers. 

NWS Operations

As Hurricane Bertha paralleled the coast, it had the potential to make its initial landfall anywhere

from Florida to North Carolina. This put extreme pressure on NHC as well as the state EMCs. 

Although NHC’s forecast tracks for Bertha proved to be quite accurate, state EMCs urged NHC

to change the location and timing of watches and warnings and to release the forecast tracks

early. This caused tension between NHC and their external users. The state EMCs thought their

input and concerns were being ignored while NHC felt that they were being second guessed on

their meteorology.

While the states agreed NHC is the technical leader and the recognized expert, the EMCs

continue to emphasize that watches and warnings are not purely a meteorological call but must

also consider emergency response and public safety. The states agree they have the authority to

issue mandatory evacuations for vulnerable coastal areas. They said that despite their efforts to

motivate people, the public will often not respond to recommendations or evacuation information

unless there is a watch or warning in effect.

Graphical representation of hurricane strike probabilities can be a useful tool, however, it was

noticed during Bertha that these graphics were not fully understood by the public or the EMCs. 

In some cases, it lead to misinformation, and in others the media was incorrectly depicting strike

probabilities. While strike probabilities work well with storms that strike the coast

perpendicularly, they were confusing when a storm parallels the coast. 
4
5

Chapter 2

National Perspectives

National Hurricane Center

Synoptic History

Hurricane Bertha originated from a tropical wave which moved from Africa to the Atlantic on

July 1, 1996. A weak circulation was first detected on satellite imagery on July 3, centered about

575 miles south of the Cape Verde Islands in the far eastern Atlantic Ocean. The track of the

circulation center begins on July 5, when the circulation is believed to have reached the surface

and become a tropical depression in the central tropical Atlantic. This track is displayed in

Figure 1 and listed in Appendix B, Table 1.

Bertha followed a fairly smooth curved path around the western periphery of the Atlantic

subtropical high pressure ridge. This ridge changed little during Bertha’s existence, and a weak

mid-level trough persisted in the western North Atlantic. For three days, the depression moved

toward the west-northwest at the fast forward speed of 23 to 29 mph. It strengthened to a

hurricane with 1-minute maximum sustained winds of 86 mph on July 8 as the center moved

across the Leeward and Virgin Islands of the northeastern Caribbean. The center moved between

Antigua and Barbuda at 2 a.m. Atlantic Standard Time (AST) (0600 Coordinated Universal Time

[UTC]) on July 8, across St. Barthelemy, Anguilla and St. Martin, just north of St. Thomas, and

over the British Virgin Islands by 2 p.m. AST (1800 UTC). 

The track gradually turned northwestward on July 9 as maximum sustained winds reached 

115 mph at 2 a.m. AST (0600 UTC). Bertha was centered 138 miles north of Puerto Rico at this

time but earlier passed within 35 miles of the island. Since the strongest winds were located in the

northeast quadrant of the hurricane, most of Puerto Rico experienced only tropical storm

conditions. The exception is the Puerto Rican island of Culebra, where hurricane-force winds are

believed to have occurred.

 

Moving northwestward at a slower forward speed of 17 to 23 mph, the center of Bertha moved

parallel to the Bahama Islands, passing 45 to 70 miles northeast of the Turks and Caicos Islands, 

San Salvador, Eleuthera and the Abacos. Again, the strongest winds were located to the

northeast of the center, but 75-mph sustained winds might have reached some of the above

mentioned islands.

Continuing on its gradual turn, the track became north-northwestward on July 10 and 11 as the

center moved parallel to the coast of Florida and Georgia at a distance of 170 to 200 miles 
6

Figure 1: Track of Hurricane Bertha, July 5-14, 1996 (extratropical track July 14-17).
7

offshore. During this time, the forward speed slowed to about 9 mph. Moving northward and reaccelerating to a forward speed of 17 mph, Bertha made landfall at 4 p.m. EDT (2000 UTC) on

July 12 on the coast of North Carolina. At landfall, Bertha was a Category 2 storm on the SaffirSimpson Hurricane Scale (see Appendix A) as the center crossed the coast midway between

Wrightsville and Topsail Beaches. The hurricane had been gradually weakening since its top

speed of 115 mph on July 9 to 81 mph on July 11. Then, 12 hours before landfall, the estimated

maximum 1-minute winds increased to 104 mph. Bertha quickly dropped below hurricane

strength when it moved inland over eastern North Carolina. Bertha then moved northeastward

along the U.S. east coast, producing 45 to 60 mph sustained winds over land from northern North

Carolina to New England. Over the nearby Atlantic, 70 mph winds were the rule. Bertha was

declared extratropical on July 14 when the center moved from the Maine coast to New

Brunswick, Canada. The extratropical storm brought 45 to 60 mph winds to the Canadian

Maritime Provinces and was tracked to just south of Greenland on July 17.

Meteorological Statistics

Figures 2 and 3 show a plot, versus time, of the various data used to estimate the minimum

central sea-level pressure and the maximum 1-minute wind speed 33 feet above ground. Included

are data from reconnaissance aircraft and satellite Dvorak-technique wind speed estimates. 

Appendix B, Table 2, lists selected surface observations of lowest pressure, peak wind, storm

surge and rainfall values. Appendix B, Table 3, lists ship reports of 39 mph or greater that were

associated with Bertha. The minimum pressure of 960 mb occurred at 2 a.m. EDT (0600 UTC)

on July 9 and is based on a dropsonde measurement. The best track maximum sustained wind

speed of 115 mph at the same time is based on a 700-mb flight-level wind speed of 140 mph,

measured 22 miles east-northeast of the center.

Observations are incomplete from the Leeward and Virgin Islands, but because the circular

eyewall was 20 to 35 miles across, it is believed that hurricane conditions with sustained wind

speeds to 86 mph could have occurred on Antigua, Barbuda, Nevis, St. Eustatius, St. Barthelemy,

Anguilla, St. Martin, and from St. Thomas northward through the U.S. and British Virgin Islands. 

Experience with Hurricane Marilyn in 1995 suggests that even higher sustained winds can occur

over mountainous terrain as is found on many of these islands. Winds 40 to 45 mph were

experienced over portions of Puerto Rico as indicated by the San Juan observations in

Appendix B, Table 2.

A reconnaissance aircraft flight level wind speed of 127 mph in the northeast quadrant of the

circulation several hours before landfall is the basis for estimating sustained surface winds of

104 mph on the coast at landfall. The lowest sea-level pressure observed at landfall was 977 mb

at Surf City, North Carolina, and a value of 974 mb is assumed to be the minimum pressure at

landfall.
8

Figure 2: Curve of minimum central sea-level pressure versus time.

Figure 3: Curve of maximum 1-minute speed versus time.
9

Coastal storm surge flood heights, from Florida through New England, ranged from 1 to 4 feet,

but values to 5 feet were estimated on the North Carolina coast from Cape Fear to Cape Lookout. 

A storm surge of 6 feet or a little higher was indicated near Swansboro, where 5 to 6 feet of water

was “inside of businesses on the waterfront” (from Newport, North Carolina, National Weather

Service Forecast Office Preliminary Storm Report). Values were forecast to be between 4-6 feet.

Six tornadoes (four in Virginia, one in North Carolina and one in Maryland) have been confirmed

during the passage of an outer rain band. 

Casualty and Damage Statistics

There were 12 deaths related to Hurricane Bertha. Four in Florida included one from an

evacuating military jet crashing into a house and three drownings from rip currents and high surf.

Two deaths were reported in North Carolina (automobile accident and rip current drowning),

while one surfer died in New Jersey. In Puerto Rico, one death occurred in an automobile

accident and another died while surfing. On the French half of St. Martin, one person was

electrocuted and another drowned after falling off a boat.

The U.S. Virgin Islands, along with North Carolina, has been declared a Federal disaster area. 

Surveys indicate that Bertha damaged almost 2,500 homes on St. Thomas and St. John. For

many, it was a second hit in the 10 months since Hurricane Marilyn devastated the same area.

It is likely that there was beach erosion on the north coast of the Dominican Republic as Bertha

passed to the north. The Bahamas were also affected by the weak side of the hurricane, but there

are no damage figures available from either of these locations.

The primary effects in North Carolina were to the coastal counties and mostly due to storm surge

flooding and beach erosion, roof damage, piers washed away, fallen trees and damage to crops. A

survey indicated more than 5,000 homes were damaged, mostly from storm surge. FEMA

estimated 250,000 persons evacuated in South and North Carolina. Minor wind damage and

flooding also spread along the path of the storm all the way to New England.

The Insurance Institute estimates $135 million in insured property damage, primarily along coastal

North Carolina. A conservative ratio between total damage and insured property damage,

compared to past land-falling hurricanes, is two to one. This would increase the total U.S.

damage estimate to $270 million. No figures are available from the Caribbean. 

Warning and Forecast Critique

Bertha moved on a fairly smooth track. The average official track forecast errors for Bertha

ranged from 92 miles at 24 hours (32 cases) to 169 miles at 48 hours (29 cases) to 258 miles at 72
10

hours (27 cases). These errors are 15 percent or more lower than the previous 10-year averages

of the official track errors and are from 15 to 40 percent lower than the CLIPER forecast errors

for the same cases.

Overall, the track model guidance also performed very well. However, the 8 p.m. EDT (0000

UTC) Aviation Model run on July 9, when Bertha was located just north of Puerto Rico,

inexplicably showed the track recurving significantly further east than the previous run. All of the

track guidance models that use the Aviation Model as a background environment also showed a

similar track. This resulted in rather large official track forecast errors on July 9, with a 705-mile,

72-hour error on the 8 a.m. EDT (1200 UTC) forecast. The Aviation Model and some of the

track guidance models recovered to an excellent forecast only 12 hours later. Fortunately, this

guidance problem occurred three days prior to landfall in North Carolina and did not have a

significant impact on U.S. warnings or on warnings for the Bahamas.

Appendix B, Table 4, lists the various watches and warnings that were issued. Hurricane

warnings were issued from Sebastian Inlet, Florida, to Chincoteague, Virginia, as well as for the

Bahamas and for the islands of the northeastern Caribbean Sea from Antigua through Puerto

Rico. Tropical storm warnings were issued from Sebastian Inlet to north of Deerfield Beach,

Florida, and from north of Chincoteague to Watch Hill, Rhode Island. Almost all of the U.S. east

coast was involved with some watch or warning which is the result of the storm track’s expected

close passage to the southeast U.S. coast. The hurricane watch for the North Carolina landfall

area was issued 65 hours before landfall, and the hurricane warning was issued 47 hours before

landfall. This is far more than the 36- and 24-hour lead times that the NHC strives for and is the

result of the forward motion decreasing at a faster rate than expected.

User Response

For about 2 days, Bertha aimed at the north-central Florida east coast. During that time, all of the

NWS track guidance models were predicting a turn to the north, near 76 degrees west. This was

uncomfortably close to some of Florida's barrier islands and Cape Kennedy which have evacuation

times exceeding 24 hours. At 11 p.m. EDT on July 9 and again during the early morning hours of

July 10, the State of Florida emergency management officials requested that NHC post a

hurricane watch for the northern parts of their east coast, but NHC hurricane specialists felt that

this was premature. On July 10, the governor issued mandatory evacuation notices at 10 a.m.

EDT, and NHC put up hurricane warnings at 11 a.m. EDT for the state, north of Sebastian Inlet. 

Early that afternoon, Bertha began its recurvature toward the north in close agreement with the

guidance models.

Similarly, South Carolina state officials became concerned about possible nighttime evacuations

on the evening of July 10 and were in great need of the latest information prior to the 11 p.m.

coordination call. The governor wanted to make a decision whether or not to order mandatory

evacuations before the 11 p.m. news. Working and coordinating closely with NWSFO Columbia,
11

NHC was called at 7:30 p.m. EDT on July 10, requesting additional forecast track information. 

This request was received more than an hour before the hurricane specialist was to begin

preparing the next forecast. The hurricane specialist and the HLT provided intermediate

information on Bertha's location and strength, however, NHC could not release any track and

intensity forecasts until the next NWS hurricane hotline call at 10 p.m. EDT, at which time the

track and intensity forecasts would be coordinated and agreed upon. The HLT believed they kept

state officials well informed regarding Bertha from an emergency management perspective. 

Hydrometeorological Prediction Center

Meteorology of Heavy Rainfall

Hurricane Bertha made landfall on the North Carolina coast on July 12 and was downgraded to a

tropical storm shortly thereafter. The storm accelerated north-northeastward across coastal

sections of the Mid-Atlantic and northeast United States prior to moving off the eastern New

England coast late on July 13. Precipitable water values increased significantly to values in excess

of 2 inches along the Eastern Seaboard as deep layered easterly flow developing in advance of the

storm advected tropical moisture inland. Heavy rain occurred from the eastern Carolinas to

Maine with many locations receiving 2- to 4-inch amounts (see Figure 4). Coastal North Carolina

and southeast New York had isolated reports of over a half foot of rain. Amounts could have

been much greater had Bertha's rapid motion not acted to limit rainfall duration. 

Guidance Products

Primary guidance that aided HPC forecasters included varied output from numerical models

(Geophysical Fluids Dynamical Lab [GFDL] model, Aviation Model [AVN], ETA Model [ETA],

Nested Grid Model [NGM], Naval Operational Global Atmospheric Prediction System

[NOGAPS], Medium-range Forecast Model [MRF], the MRF ensemble package, Medium-range

Forecast Model Experimental [MRFX], European Center for Medium Range Weather

Forecasting [ECMWF], United Kingdom Meteorological Office [UKMET], meso-ETA, NHC

hurricane models, etc.), satellite imagery (Geostationary Operational Environmental Satellite

[GOES]-8/9 Visible [VIS], Infrared [IR], Water vapor [WV], and Special Sensor Microwave

Imagery [SSMI] microwave data), NEXRAD data, surface and upper-air observations and

aircraft reconnaissance data.

Model output was varied. While all models correctly indicated the potential for heavy rainfall

over the eastern United States, the AVN forecast a Bertha track and associated quantitative

precipitation forecast (QPF) that was shifted farther to the west than the ETA or NGM. The

AVN track implied that a significant upslope rain event was imminent in the favored upslope

region on the eastern side of Appalachian Mountains. The ETA and NGM supported a heavy

rainfall event farther to the east. Weather pattern recognition and upper-air data analysis
12

combined with trends from satellite imagery and radar to prompt HPC forecasters to prefer a

solution close to but wetter than that depicted by the ETA. Subsequent observations deemed that

our model assessments were on the right track.

HPC staff produced an array of graphic products and accompanying narratives. These products

provided an assessment of guidance and an excellent forecast of quantitative precipitation, flash

flood potential and the sea level pressure pattern from current conditions up to five days

(see Figures 5-7).

Internal Coordination

HPC forecasters participated in at least four regularly scheduled hurricane coordination calls each

day that included verbal input from NHC, SPC, MPC, WFO's, WSH, SRH, ERH, Naval Atlantic

Meteorology and Oceanography Center at Norfolk, Virginia, and the Naval Meteorology and

Oceanography Facility at Jacksonville, Florida. Information discussed included Bertha's forecast

strength and track from zero to five days and associated QPFs. Routine coordination calls were

also performed with FEMA.

Marine Prediction Center

Marine Meteorology

As Bertha moved along the east coast recurving across the Maritimes and then well out to sea, it

created significant marine meteorological conditions for an extensive segment of the MPC High

Seas area of responsibility. The most notable conditions are chronicled below.

# As Bertha passed near the Bahamas on July 10 at 8 a.m. AST (1200 UTC), well before the

center entered MPC's area, 13-foot southerly swells had propagated as far north as 34N west

of 69W.

# On July 11 at 8 a.m. AST (1200 UTC), while hurricane and tropical storm force winds

remained south of 32N, the southern limit of the MPC forecast area, seas increased to 20 feet 

over the area south of 34N west of 70W. Near gale force winds extended out to 520 miles

over the north semicircle.

# By July 12 at 8 a.m. EDT (1200 UTC), the center of Bertha had crossed 32N, approaching

the coast of the Carolinas. Packing maximum sustained winds of 104 mph, the storm

generated a maximum wave height estimated at 39 feet just south of Frying Pan Shoals. 

# On July 13, Bertha moved inland across eastern North Carolina and southeast Virginia,

weakening to a tropical storm with sustained winds of 52 mph and gusts to 63 mph at 8 a.m.

EDT (1200 UTC). Winds near tropical storm force and 13-foot seas also occurred within 485

miles from the center.
13

Figure 4
14

Figure 7: Revised Quantitative Precipitation Forecast Guidance - 2 am, July 13.

Figure 6: Quantitative Precipitation Forecast Guidance - 8 am, July 14.

Figure 5: Quantitative Precipitation Forecast Guidance - 8 am, July 13.
15

# By July 14 at 8 a.m. EDT (1200 UTC), Bertha had lost most of its tropical characteristics and

was declared extratropical, becoming the sole responsibility of the MPC. Located along the

New Brunswick coast, storm force winds to 63 mph and seas to 20 feet occurred within 485

miles over the southeast semicircle. Gale force winds and seas to 16 feet extended out to 620

miles over the southeast semicircle and 345 miles over the northwest semicircle.

# On July 15 at 8 p.m. EDT (0000 UTC), former Bertha was downgraded from an extratropical

storm to a gale, still packing winds to 52 mph with seas to 18 feet southeast of the center.

# As the low moved northeast across the open ocean, gale warnings were continued until

July 17 at 2 a.m. EDT (0600 UTC). Through its final weakening stages as a gale from

Newfoundland to just south of Cape Farewell, an extensive area of 13- to 21-foot seas

continued east and south of the center.

Forecast and Guidance Products

MPC forecast and analysis products are routinely broadcast to ships at sea. This is done through

the U.S. Coast Guard high frequency communication facilities. The products consist of high seas

text bulletins and graphic surface analysis and forecast products. In addition, voice broadcasts of

warnings and forecasts which originate at the MPC are broadcast over station WWV, Boulder,

Colorado. Although all of these products are produced according to a regular schedule, they all

contain warning and forecast information as provided in the official TPC bulletin.

The frequency of transmission for these products is every 6 hours and is based on the synoptic

reporting times (0000 UTC, 0600 UTC, 1200 UTC, 1800 UTC).

Coordination

Coordination took place using the Hurricane Hotline or through telephone calls. TPC's

conference calls were routinely monitored and telephone calls to TPC's Tropical Analysis and

Forecast Branch were made for purposes of coordination. In anticipation of the system becoming

extratropical and to cover expected conditions in offshore waters, MPC provided input for

adjustments of TPC's tropical force wind/12-foot seas radius as the storm crossed north of 32N

prior to making landfall along the southern North Carolina coast. The input was accepted and

incorporated into the advisory.
16

Storm Prediction Center

Forecast and Guidance Products

Tornado watches associated with Bertha (see Appendix D).

Tornado Watch issue (CDT) valid end

 764 12/9:37 a.m. 10:00 a.m. 7:00 p.m.

 765 12/1:36 p.m. 2:00 p.m. 7:00 p.m.

 768 12/6:16 p.m. 7:00 p.m. 4:00 a.m.

 770 12/11:41 p.m. midnight 7:00 a.m.

 771 13/3:00 a.m. 3:15 a.m. 10:00 a.m. (replaced 768 and 770)

 772 13/12:20 p.m. 12:45 p.m. 7:00 p.m.

Mesoscale Meteorology and Coordination

The SPC participated in all hurricane hotline discussions concerning Bertha during its lifetime,

however, this was due to the fact that SPC forecasters were monitoring the hotline. NHC failed

to roll call the SPC nor did it invite input from the SPC. NHC should include the SPC in its roll

call list for coordinating advisories when a tropical cyclone threatens the U.S. mainland. During

the 10 a.m. EDT coordination on July 12, the SPC forecaster commented that the tornado threat

for the east coast was increasing and that he should probably issue a tornado watch (the first in a

series). The hurricane specialist suggested that the SPC handle the details off-line with the

individuals involved, and that he would mention the possibility of tornadoes in the next bulletin. 

After the hotline call ended, the SPC forecaster called the offices in Raleigh, North Carolina, and

Columbia, South Carolina, to coordinate the tornado watch (No. 764) which extended from

northeastern South Carolina into southeastern and east-central North Carolina. 

During the course of the morning and early afternoon, several tornado warnings were issued in

North Carolina with some occurring near the western and northern boundaries of the watch. 

Damage was reported with a thunderstorm near Raleigh. Since there was a strong surface high to

the north (1026 mb center), the resulting pressure gradient was producing relatively strong low

level flow (and shear) well to the north of the tropical storm center. Further, instability along and

east of a surface trough extending from eastern North Carolina into southeastern Virginia had

reached moderate values. These factors raised the concern that the tornado threat would be

developing northward along and east of the trough line during the afternoon hours and that a

watch would be needed northward from the original watch into southeastern Virginia. To make it

simpler for the NWSFOs and NWSOs, the ending time 8 p.m. EDT (0000 UTC) was chosen to be

the same as that with the original watch. The SPC forecaster called NWSFOs Raleigh, North

Carolina, and Sterling, Virginia, to propose the new watch (No. 765). SPC mentioned that there

was rotation with a cell on the Virginia/North Carolina border and that NWSO Wakefield,

Virginia, had issued a tornado warning as a result. All agreed to the watch although Sterling was
17

a little hesitant. On several occasions, the SPC noted that it is apparent that during hazardous

weather events when staffs at local offices are busiest, it can be difficult for them to stay abreast

of evolving and immediate post-weather events in nearby NWSFOs/NWSOs areas of

responsibility. Later in the evening, tornado watch Nos. 768 and 770 were issued as the tropical

system tracked north.

By early Saturday morning, July 13, the main east-west "spiral band" of isolated supercells which

was over northern Virginia continued northward and had reached a northern Maryland/southern

New Jersey line by around daybreak. Two rotating storms on the far western end of this activity

were edging dangerously close to the western edge of the previous weather watch and nearing the

eastern suburbs of Washington, D.C. Therefore, upon consultation with NWSFOs Sterling,

Virginia; Philadelphia, Pennsylvania; and New York City, New York, the SPC forecaster decided

to issue a new watch (No. 771) which covered a bit more of the "western shore" region of the 

Chesapeake Bay. Shortly after the watch was issued, a new thunderstorm began to rotate along

the same spiral band which had produced the rotating storms east of Washington. This latter cell

moved right across Baltimore and prompted a tornado warning from Sterling, but no tornadoes

were reported.

During the coordination call for Tornado Watch No. 771, NWSFO Philadelphia had no trouble

accepting the watch as there had already been isolated rotating storms over Delaware Bay earlier.

These storms were well in advance of the Virginia/Maryland spiral band. On the other hand,

NWSFO New York City really didn't want the watch (No. 771), but they were unaware of the

fact that isolated supercells had been occurring as close to them as Delaware Bay earlier. There

was good agreement with NWSFO Boston, Massachusetts, to the effect that any tornado threat in

New England would be delayed for a while due to the presence of cooler/drier air near the surface

(dew points were in the 60s vs. low to mid 70s in Maryland). As has been pointed out in several

instances, the long standing procedures of watch coordination with field offices were, in general,

effective. The coordination process provided the field with opportunities to contribute and, in

most cases, coming to a consensus was not a problem. The SPC also noted the ability to dial into

the WSR-88Ds that were being affected proved to be a valuable tool in assessing the tornado

threat from Bertha.
18
19

Chapter 3

Regional Perspectives

Southern Region

# Puerto Rico and the U.S. Virgin Islands

Data Collection

WSR-88D

Performance of the San Juan WSR-88D, an FAA radar, was acceptable as Bertha moved across

the Virgin Islands and north of Puerto Rico. However, as of Saturday, July 6, the radar was

inoperative with no apparent plans to return it to service. Representatives from SRH, WSH,

Office of Systems Operation, and the Operational Support Facility spent several hours during the

evening of July 6 coordinating and attempting to isolate the problem. On the morning of July 7,

the FAA electronics technician (ET) had identified the problem as irregular fluctuations in the

frequency of the generator used to power the RDA. Due to the remoteness of the site, the RDA

does not have commercial power. The permanent fix to the generator’s problem was to install an

electronic governor on the generator, but this could not be done before Bertha’s arrival. The

FAA ET would attempt to temporarily stabilize the signal on a short-term basis but could not

promise any definite success. The efforts were in fact successful as the WSR-88D remained

operational for the duration of the event. Once the scope of the WSR-88D problem was made

known to the appropriate FAA representatives, they were cooperative and restored the radar to

service as quickly as possible.

Automated Surface Observing System (ASOS)

The ASOS units on St. Thomas and St. Croix functioned normally until Monday, July 8. On the

morning of July 8, the control towers at both islands’ airports were abandoned. FAA personnel

have instructions to power down all equipment, including ASOS, when the towers are abandoned. 

Thus, no ASOS data were available as the storm impacted the islands, and no official wind or

pressure data were available in real-time or after the event. The ASOS at San Juan remained

operational, recording a maximum wind gust of 60 mph and a minimum pressure of 996.8 mb.
20

Warning and Forecast Services

NWSFO San Juan began issuing HLSs at 11:20 p.m. AST, Saturday, July 6. The HLSs were

issued at 6 hourly intervals through 5 p.m. on July 7, at which time they switched to 3 hourly

statements. The statements contained a great deal of information presented in a segmented form

as recommended by the Hurricane Marilyn Disaster Survey Report. Separate sections of the

HLS were used to describe preparedness actions, the storm’s position, storm surge, etc. This

enabled customers to quickly find information regarding a particular aspect of the storm’s threat. 

As Bertha approached and moved by Puerto Rico, HLSs were composed and disseminated every

2 hours. These HLSs were a marked improvement over those issued for Hurricane Marilyn. 

NOWs were prepared by NWSFO San Juan throughout the event. The NWSFO staff utilized

information primarily from the WSR-88D when composing their NOWs. While the NOWs were

informative, some of them were written in a style similar to the radar narrative summary (i.e., “At

xxx pm...radar indicated the center of Bertha...”). This had the effect of dating the products and

focusing customers’ attention to the storm’s history rather than its forecast track and impacts.

Dissemination and Coordination

NWSFO San Juan communicated information regarding Bertha in a variety of ways. The primary

dissemination means were NWR and NWWS. Local EMCs and media took an active role in

relaying information to the citizens, using methods ranging from facsimile transmissions to live

television and radio broadcasts.

On St. Thomas, NWR broadcasts are provided through a service contract with radio station

WAH. Normally, WAH provides NWR service between 6 a.m. AST and midnight. However,

with the approach of Bertha, WAH conducted 24-hour operations from one day before the

storm’s arrival to two days after Bertha’s impact. The St. Thomas office of the Virgin Islands

Territory Emergency Management Agency (VITEMA) has the “state” NWWS drop provided by

the NWS. The system was operational until mid-afternoon Monday, July 8, when power was lost

to the VITEMA facility. The VITEMA-St. Thomas office was in frequent contact with NWSFO

San Juan, as coordination calls were held at least five times daily starting on Friday, July 5.

On St. Croix, VITEMA officials were still not receiving all NWWS products from the drop on St.

Thomas. However, the St. Croix staff obtained the necessary information via coordination calls

with the NWSFO San Juan, the Internet, The Weather Channel, and the VIFreenet. The

VIFreenet is a free Internet-based service for Virgin Islands citizens. The service is maintained by

private sources. VITEMA-St. Croix staff also gathered weather information from the FEMA

Region I HF radio network. Although some problems were encountered with the NWWS, the

VITEMA-St. Croix staff utilized multiple dissemination methods to receive information regarding

Bertha.
21

Preparedness

As in previous years, the staff at NWSFO San Juan conducted an aggressive hurricane

preparedness campaign. From October 1995 through June 1996, the office participated in

48 conferences, workshops, seminars, presentations and interviews related to hurricane

preparedness. Among these activities was a 2-day workshop, conducted in cooperation with

TPC/NHC, for VITEMA officials. The office also conducted an in-house hurricane seminar

which was also attended by two members of the VITEMA-St. Croix staff. NWSFO continues

their noteworthy preparedness efforts.

Customer Response

The local media was proactive, especially the print media outlets. The St. Croix Avis, the local

newspaper on the island, covered Bertha as their headline story beginning on Saturday, July 6. 

NWS Public Information Statements documenting preparedness activities were printed in the

Sunday and Monday (July 7 and 8) editions. VITEMA officials on both St. Thomas and St. Croix

were satisfied with the information they received during the event, including the forecast track and

intensity. Although Bertha was a fast-moving storm as it approached the islands, VITEMA staff

and citizens felt they had ample time to prepare. Thus, the VITEMA staff believed that they

received better services than during Hurricane Marilyn in 1995.

# Florida and Georgia

Data Collection

All of the data collection equipment in place along the Florida and Georgia coasts was operational

during the event. The WSR-88D, ASOS, upper air equipment, and data buoys performed well

throughout Bertha’s trip up the east coast.

However, NWSFO Miami, Florida, noted a problem with a lack of data off the southeast Florida

coast. Without the data, no wave information is available south of Melbourne, Florida. Wave

heights can be estimated from local wind forecasts, but no observations of swells are routinely

available and no “ground truth” wind/wave data can be accessed by forecasters. The NWSFO

Miami WCM has talked to the Beach Patrol units in southeast Florida, asking them to call in

rough surf reports to the office. This practice is not consistently done.

Warning and Forecast Services

All coastal offices issued frequent HLSs for their areas of responsibility. The HLSs roughly

coincided with the release of advisory packages or intermediate advisories from TPC/NHC. 
22

Because Bertha remained well away from the coastline, none of the Florida coastal offices needed

to document the storm’s progress in short term forecasts (NOW).

During the evening of July 9, Bertha approached southeast Florida and TPC/NHC issued the

Tropical Storm Warning from Deerfield Beach, Florida, northward. This was upgraded to a

Hurricane Warning from Sebastian Inlet northward during the morning of July 10. NWSFO

Miami, NWSO Melbourne, and NWSO Jacksonville, Florida, began issuing HLSs at around

midnight on July 10. The HLSs were issued about every 3 hours until the warnings were

discontinued (5 p.m. EDT on July 10 for Miami, 5 a.m. on July 11 for Melbourne, and 5 a.m. on

July 12 for Jacksonville). Overall, the offices’ HLSs were detailed and accurate. In cases where

the HLSs were lengthy, a segmented approach was used. As at NWSFO San Juan, the Florida

offices’ segmented HLSs contained separate paragraphs discussing topics such as the storm itself,

evacuation instructions, and tide information. It should be noted that all of Florida’s coastal NWS

offices issued timely and informative HLSs as Bertha passed offshore.

In addition to the HLSs, NWSFO Miami issued heavy surf advisories and statements advising of

rough surf conditions and potential strong rip currents through July 12. Unfortunately, one death

occurred on July 10 due to a rip current off Jacksonville Beach. Later in the week, due to the

lack of wave/swell data from off the southeast coast, the heavy surf advisory was prematurely

canceled. Two more people were drowned and more than 100 were rescued along Dade County

beaches on July 12 and 13 due to rip currents caused by swells from Bertha. The NWSFO Miami

also issued a wind advisory on the morning of July 10 for inland portions of central and southern

Florida with winds forecast to 35 mph. The wind advisory was extended to portions of northcentral Florida during the late morning of July 10.

Internal and External Coordination

Although Bertha’s meteorological impacts on the Florida and southeast Georgia coasts were

minimal in the form of heavy surf and minor beach erosion, the storm was the subject of tense

coordination between NHC and the State of Florida EMC. Because the NHC forecasters felt that

the storm would turn to the north and eventually to the northeast, no watches or warnings were

originally issued for the coast. By Tuesday, July 9, the storm still had not made an appreciable

turn to the north. During a coordination with the state EMC on the evening of July 9, the state

EMC virtually insisted that a watch or warning be issued so that their coastal county EMCs could

initiate their hurricane plans. The storm still had not made an appreciable turn by the morning of

July 10. During the 10 a.m. EDT conference call between NHC and the local offices, it was

agreed that an upgrade to a hurricane warning was the best course of action. Bertha finally

slowed and started to turn north by the afternoon of July 10, but the warnings were left up for

precautionary reasons. In retrospect, the NHC official forecasts were accurate in depicting

Bertha’s decrease in forward speed and turn to the north. Although the turn did occur, the

uncertainty involved with the forecast made coordination with the State of Florida EMC difficult.
23

The local offices along the coast were active in coordinating with their local emergency

management officials. Staffs at the offices were involved with both the NHC coordination calls

and the State of Florida conference calls as well. Offices utilized telephone and amateur radio

communication when needed to elaborate on the information contained in HLSs.

Customer Response

Despite the coordination issues which occurred during Bertha’s approach, local customers were

satisfied in general with the services they received. The Palm Beach County EMC was supportive

of the NWS warnings and forecasts and expressed displeasure only at the tenseness of the

coordination between NHC and the state EMC. The Broward County EMC was concerned about

the breakpoint chosen for the tropical storm warning (north of Deerfield Beach) since Deerfield

Beach is in Broward County but the warning was for the area north of Broward County.

Along the central Florida coast, there was some second-guessing of the warnings and evacuations. 

These concerns were especially evident in the local print media. However, the majority of the

customers in the area felt that the actions taken were prudent considering the history and past

track of the storm. The NWSO Melbourne WCM has engaged in ongoing meetings with local

emergency managers to evaluate the communication and coordination issues. 

In northeast Florida and southeast Georgia, customers were satisfied as well with the services

from NWSO Jacksonville, Florida. The regional media were centrally located in the Duval

County EMC. On the afternoon of July 10, the NWSO Jacksonville MIC relocated to the Duval

County, Florida, EMC to field media inquiries and to enhance coordination with Duval County

and other local emergency management officials. Community response in the coastal areas was

immediate upon issuance of the hurricane warning. NWSO Jacksonville received a letter of

appreciation from the Camden County, Georgia, EMC, and several other local agencies gave

verbal compliments to the office. As in east-central Florida, the NWSO Jacksonville WCM and

SOO have engaged in frequent evaluation meetings with local customers.

Eastern Region

Impacts

Hurricane Bertha was an unusual early season Category 2 hurricane which made landfall near

Wrightsville Beach, North Carolina. Bertha was the first significant hurricane to directly affect

the state between Wilmington and Morehead City since Hurricane Donna in 1960.

The American Insurance Association estimates that $135 million of insured property losses

occurred during Bertha with $100 million having occurred in North Carolina, $25 million in

Virginia, and $10 million in South Carolina. Claims represent insured losses resulting from

factors other than tidal inundation (i.e., mostly wind).
24

The hardest hit area was just to the east of the eye at landfall...Topsail Beach and Swansboro,

North Carolina. Water was 5 to 6 feet deep in waterfront businesses in Swansboro. Highest wind

gusts reported on land were 108 mph at Camp Lejeune and Jacksonville and 95 mph at

Wrightsville Beach (all in North Carolina). Wind gusts of 80 mph were observed at NWSO

Newport, North Carolina. In Wilmington, North Carolina, just to the west of the eye, winds

gusted to 70 mph. Over water, the Frying Pan Shoals C-Man tower, 35 miles off the North

Carolina coast, registered a gust to 115 mph. NWSO Wilmington, North Carolina, recorded

5.66 inches of rain during Bertha's passage.

In North Carolina, moderate to severe amounts of beach erosion occurred in areas of Bertha's

greatest impact. Mason Inlet lost 50 feet of land, leaving the inlet that much closer to Shell Island

Resort. At Emerald Isle, the dunes dropped vertically 8 to 10 feet at the erosion line. At Kure

Beach, there was 4 feet of vertical erosion against the boardwalk, leaving the strand narrower by

40 feet. On the Outer Banks, more than 150,000 people (mostly tourists) evacuated back to the

mainland. Further south, well over 100,000 people evacuated to the west of I-95 and out of

harms way.

Outside the areas of greatest impact, Bertha's effects were much less dramatic. In South Carolina,

the highest measured wind was at the downtown Charleston Handar with a peak gust of 58 mph. 

Higher peak gusts likely occurred along the barrier island beachfronts. No significant beach

erosion occurred as the maximum tide departure occurred near the time of low tide. Rainfall was

generally between 1 and 2 inches. Widespread power outages occurred over North Carolina with

as many as 250,000 customers without power in the eastern portions of the state. About 80,000

people were evacuated in South Carolina and 20,000 in Georgia. Revenue losses due to

evacuations of tourists and residents were estimated to be about $40 million. One person

drowned off Myrtle Beach in advance of the storm while attempting to surf the large waves and

swells.

In Virginia, four tornadic storms associated with Bertha resulted in much of the damage across

eastern portions of the state. The strongest tornado struck Northumberland County, Virginia, and

resulted in nine injuries. Rainfall totals ranged from 3 to 6 inches on the Virginia Capes and the

lower Maryland shore to 2 to 4 inches over inland sections of Virginia east of Interstate 95. 

Mostly minor to locally moderate tidal flooding and beach erosion occurred. Extensive power

outages occurred over eastern Virginia, with as many as 115,000 customers without power in the

eastern sections of the state. In the NWSO Wakefield, Virginia, county warning area (CWA),

nearly 1,800 people were evacuated.

Inland portions of Delaware and Maryland experienced heavy rain and gusty winds from what was

now Tropical Storm Bertha although the most significant impact was from several weak

tornadoes. There was some attendant wind damage associated with the stronger thunderstorms in

Bertha's rain bands. The Patuxent River, Maryland, Naval Air Station recorded a gust of 48 mph

and 4.03 inches of rain. Rainfall totals ranged from 4 to 4.5 inches along the western shore of the

Chesapeake Bay and 1 to 2.5 inches across metropolitan Washington, D.C. In Bertha's aftermath,
25

about 2,000 homes were without power in northern Virginia, 5,000 around the District of

Columbia and surrounding Maryland suburbs, and 10,000 in and around Baltimore.

In New Jersey, the most significant impact from Bertha was the heavy rain with 2- to 4-inch storm

totals common in coastal sections, with a few isolated reports greater than 6 inches. One such

report was 6.69 inches in Estelle Manor, New Jersey. Generally, coastal and flash flooding were

not a problem although moderate wave action was responsible for one surfing fatality. Harvey

Cedars, New Jersey, reported a 63-mph gust with some downed trees and resultant power

outages which were a consequence of the area's experiencing strong gusty winds and saturated

soils.

On Long Island, winds gusted to 64 mph on Babylon Village, New York. Rainfall totals were as

high as 4.65 inches at Pomona in Rockland County, New York. In New York City and Long

Island, rainfall amounts ranged from 0.76 inches in Quogue to 2.49 inches at Mt. Sinai (both on

Long Island). Mostly minor to locally moderate beach erosion occurred.

In southern New England, most of Bertha's adverse effects were minimal and resulted in only

minor coastal flooding. One strong band of convection, however, resulted in strong winds and

numerous power outages across Rhode Island and southeast Massachusetts. The highest reported

gust was 87 mph in New Bedford, Massachusetts. The maximum reported rainfall was

7.20 inches at Billerica, Massachusetts. Rainfall totals exceeded 5 inches at several locations in

northern Rhode Island, northeast Connecticut and interior parts of eastern Massachusetts.

The remainder of New England essentially had to deal with the locally heavy rains associated with

Bertha's remnants. Total rainfall across the area was generally in the 2- to 4-inch range with

lower amounts in northern Maine and northern New Hampshire. There were several reports of

water over the roads in the areas covered by flood warnings, but no significant problems or

damage was reported. (See Appendix E for the Aerial Survey.)

Warning and Forecast Services

Timely hurricane watches and warnings were posted commensurate with the threat posed by

Bertha. However, intensity forecasts prior to landfall in North Carolina were not on target. 

Information from NHC indicated that Hurricane Bertha had weakened as she approached the

North Carolina coast. The hurricane had been gradually weakening since its top speed of

115 mph on July 9 to 81 mph on July 11. Then 12 hours before landfall, the estimated maximum

1-minute winds increased to 104 mph. Information relayed to eastern North Carolina emergency

managers mirrored information received from the NHC. Forecast wind speeds, especially inland,

were too low.

Forecasts of sound-side flooding of the Outer Banks were based on a numerical model developed

at North Carolina State University. The forecast based on the late afternoon advisory on July 11
26

called for a 6- to 8-foot surge. This forecast did not take into account decreasing wind speeds as

Bertha moved north through eastern North Carolina. As a result, the surge forecast was too high. 

Actual surges were on the order of 1 to 2 feet. South of this area from Cape Lookout to Cape

Fear, the storm surge was between 5 and 6 feet and was forecast to be between 4 and 6 feet.

Some lower Maryland Eastern Shore emergency managers expressed concern with the lack of a

Hurricane or Tropical Storm Watch north of the Hurricane Warning area. It was their feeling that

a Watch would have afforded them the freedom to take action commensurate with the level of

threat they perceived existed.

Further north, local NWSFO and NWSO products were excellent and accurately depicted the

hazards posed by the now weakening tropical storm. Early on in the event, there was some initial 

forecast disagreement across southern New Hampshire. This was subsequently resolved by a joint

telephone call with the New Hampshire Office of Emergency Management by staffs at NWSFOs

at Taunton, Massachusetts, and Gray, Maine. Generally, the accurate and timely NWS warnings

and forecasts allowed customers both on land and water to adequately prepare for Bertha.

Internal and External Coordination

Internal NWS and external coordination during Bertha's passage through Eastern Region went

well in most instances. Timely notification to Federal, state, county and local agencies were

initiated by local NWS offices well in advance of the official watches and warnings. This ensured

that users were well-prepared days in advance of the hurricane's impact.

External coordination was accomplished primarily via telephone. Some users in the heart of

Bertha's path obtained information through a bulletin board system at NWSO Newport, North

Carolina. The primary backup system at the NWSO, amateur radio operators, was used to gather

information but was not needed for coordination purposes since the telephone system did not fail.

Internal NWS coordination was accomplished primarily via telephone, the hurricane hotline, and

AFOS.

Some user complaints were also received regarding the utility of the inland winds model. As

noted earlier, this largely resulted from the forecast of strong inland winds in the NHC marine

advisory not reflecting observed conditions.

In northeast North Carolina, the hurricane revealed some coordination problems with regard to

the timely dissemination of important weather information between NWSO Wakefield, Virginia,

and the emergency managers of the coastal counties within Wakefield’s CWA. The MIC and

SOO met with the emergency managers and resolved these issues. Additionally, emergency

management officials stated they continue to have tight budgets and cannot afford NWWS. 

EMWIN was emphasized while the use of Internet and the bulletin board service was mentioned.
27

In North Carolina, some problems were noted regarding NHC initiated calls to the EMC. When a

hurricane warning is posted for the North Carolina coast, the NWSFO Raleigh MIC and WCM

brief the state EMC in person when each new advisory is issued. State emergency management

officials also call the NWSFO as appropriate, between visits by the MIC or WCM, to get

intermediate updates on the hurricane's progress. NHC briefing calls frequently came at times

when state officials were already in the midst of a briefing by the NWSFO or with local

emergency management officials along the coast. 

At a number of NWS offices, HAM radio SKYWARN volunteers received and passed along

information. In at least one instance (NWSO Wilmington, North Carolina), Packet Radio was

their primary communication device. Local emergency management officials with Packet Radio

often received the hurricane advisories and local office statements more than a half hour before

they were received by other means. Additionally, the Packet Radio also provided them with

Doppler (WSR-88D) radar images from the radar coded message product.

Data Collection and Communication

The coastal portion of the NWSO Morehead City, North Carolina, CWA is covered with data

collection devices ranging from ASOS sites, Datalogger, and DARDC wind equipment. Most

units failed once power was lost. Amateur radio operators were used to gather information

throughout the storm and proved to be NWSO Morehead City's most reliable data-gathering

source. Generally, though, the sparsity of land and over water real-time observations proved once

again to be an obstacle as Bertha slammed onshore and traversed through eastern North Carolina.

Local NWS office work on fine-tuning the WSR-88D rainfall estimates continued during Bertha. 

With the passage of each tropical system through the region, more radar data are helping local

offices to fine tune the most accurate reflectivity (Z-R) relationship to utilize. This will aid

NWSFO/NWSO assessments of the (rainfall) flooding potential during future tropical system

passages.

WSR-88D level II, III, and IV data were archived by NWS offices in Bertha's path. 

Unfortunately, the archive level II data at NWSO Morehead City was inoperative throughout the

event. In addition, many NWSFOs and NWSOs archived upper level plots, surface observations

and model gridded data during the hurricane.

In North Carolina, the New Bern and Cape Hatteras NWR failed for a time as the hurricane was

reaching peak strength. This is a problem which the Region is attempting to minimize for future

hurricanes and other severe weather episodes through the use of NWS-owned and operated

uninterruptible power supply and back-up generator equipment at NWR transmitter locations.

A number of offices noted a truncation of some of the more lengthy HLS on TWC. Moreover, it

was also noted that some of the NOWs were cut off at six, as opposed to eight lines. Obviously,
28

this premature truncation of the HLS and NOW will result in need-to-know information not being

passed on to the viewer and as such needs to be resolved with TWC.

A telephone company problem led to the NWR's Blue Hill transmitter, which serves the Greater

Boston area, being off the air for several hours during the height of the storm. Additionally, the

Providence ASOS temperature and dew point sensor went out of service during Bertha's passage

through the area.

User Response

User response was quite good. The successful evacuations and low casualty rates reflect the

growing sophistication and team efforts of the NWS and the emergency management community

although a number of false perceptions as pertains to the hurricane's perceived threat linger.

Emergency management personnel in North Carolina are well trained and made the appropriate

evacuation decisions. All used either the "HurrTrak" or "Hurrevac" computer software to aid in

their decision-making process. Conference calls that included all emergency managers as well as

NWSO Morehead City and NWSO Wakefield personnel were initiated by the North Carolina

Area A Coordinator (includes northeastern North Carolina counties). Occasional conference calls

were initiated by the Area C Coordinator (central and southeastern North Carolina counties).

The media and public responded quite well. Most tourists evacuated when ordered, however, the

majority of the year-round residents remained on the North Carolina barrier islands.

Further north, the states of Maryland and Virginia were contacted after the event to assess their

reaction. Feedback from the state level was strongly positive. Some concern was expressed by

one emergency manager on the Maryland Eastern Shore, regarding the NWS use of one of the

hurricane break points during the event.

Just to the south of Bertha's greatest impact, individuals who were not allowed to return to

evacuated areas immediately after the hurricane and subsequently saw only limited damage noted

that they would not evacuate when the next hurricane approached. This attitude is a continuing

problem that the NWS and FEMA will have to resolve in present and future educational outreach

efforts.

Preparedness

The true measure of a warning program's effectiveness is the degree of response that the warning

elicits from the public and local officials. The NWS must work closely with emergency managers,

officials and the media to gain their trust and to ensure that their requirements for technical
29

information are met. Similarly, active public awareness campaigns conducted with local officials

and the media foster heightened awareness of hazards presented by hurricanes.

Numerous pre/early season hurricane preparedness activities were conducted throughout the

Region prior to Bertha making landfall in North Carolina and then moving up the east coast, a

short distance inland. Most individuals knew how to respond to Bertha's threat, and thereby

demonstrated that NWS community preparedness/outreach efforts indeed paid off. It was

interesting to note, however, that North Carolina Preparedness Week was scheduled in North

Carolina for the week following Bertha’s passage. Needless to say, the week's activities were

canceled in lieu of the "real-life" experiences associated with this early season hurricane.

In South Carolina, working relations with local and state emergency managers are in excellent

condition thanks to regular South Carolina Hurricane Task Force meetings and work

accomplished through the local NWSO Charleston and NWSFO Columbia preparedness

programs. Similar actions at other Eastern Region coastal NWSFOs/NWSOs translated to

successful local preparedness efforts during the days leading up to Bertha's passage through the

Region.

During state conference calls, the state and local officials displayed reasonable expectations and

asked pertinent questions of the local office NWS participants. These emergency managers

seemed to understand well the role local NWSFO and NWSO offices play and used NWSprovided information to their full advantage.

Finally, Eastern Region NWSFOs and NWSOs were well prepared internally for Bertha with

appropriate staffing changes initiated well in advance of the hurricane/tropical storm. This

ensured that local NWS offices were properly staffed to meet the challenges posed by this

hurricane. Externally, shelters were opened where needed, and again, no preparedness problems

were noted.
A-1

Appendix A

Saffir-Simpson Hurricane Scale*

Category Definition—Likely Effects

ONE Winds 74-95 mph: No real damage to building structures. Damage

primarily to unanchored mobile homes, shrubbery, and trees. Also, some

coastal road flooding and minor pier damage.

TWO Winds 96-110 mph: Some roofing material, door, and window damage to

buildings. Considerable damage to vegetation, mobile homes, and piers. 

Small craft in unprotected anchorages break moorings.

THREE Winds 111-130 mph: Some structural damage to small residences and

utility buildings with a minor amount of curtainwall failures. Mobile homes

are destroyed. Flooding near the coast destroys smaller structures with

larger structures damaged by floating debris. Terrain may be flooded well

inland.

FOUR Winds 131-155 mph: More extensive curtainwall failures with some

complete roof structure failure on small residences. Major erosion of

beach areas. Major damage to lower floors of structures near the shore. 

Terrain may be flooded well inland.

FIVE Winds greater than 155 mph: Complete roof failure on many residences

and industrial buildings. Some complete building failures with small utility

buildings blown over or away. Major damage to lower floors of all

structures located near the shoreline. Massive evacuation of residential

areas may be required.

 

 In operational use, the scale corresponds to the 1-minute average sustained wind speed as *

opposed to gusts which could be 20 percent higher or more.
B-1

Appendix B

Meteorological Tables








C-1

Appendix C

Fujita Tornado Intensity Scale

Category Definition-Effective

(F0) Gale tornado (40-72 mph): Light damage. Some damage to chimneys; break

branches off trees; push over shallow-rooted trees; damage sign boards.

(F1) Moderate tornado (73-112 mph): Moderate damage. The lower limit is the

beginning of hurricane wind speed; peel surface off roofs; mobile homes pushed off

foundations or overturned; moving autos pushed off the roads.

(F2) Significant tornado (113-157 mph): Considerable damage. Roofs torn off

frame houses; mobile homes demolished; boxcars pushed over; large trees snapped

or uprooted; light-object missiles generated.

(F3) Severe tornado (158-206 mph): Severe damage. Roofs and some walls torn off

well-constructed houses; trains overturned; most trees in forest uprooted; heavy

cars lifted off ground and thrown.

(F4) Devastating tornado (207-260 mph): Devastating damage. Well-constructed

houses leveled; structure with weak foundation blown off some distance; cars

thrown and large missiles generated.

(F5) Incredible tornado (261-318 mph): Incredible damage. Strong frame houses

lifted off foundations and carried considerable distance to disintegrate; automobile

sized missiles fly through the air in excess of 100 yards; trees debarked; incredible

phenomena will occur.
D-1

Appendix D

Storm Prediction Center

Tornado Watch Areas






E-1

Appendix E

Aerial Survey

Introduction

Hurricane Bertha struck the North Carolina coast on the afternoon and evening of July 12, 1996. 

I arrived in Wilmington, North Carolina, on Monday, July 15. During the afternoon of July 15, a

flight was made on the NOAA Aircraft Operations Center (AOC) DeHavilland Twin Otter. An

aerial flight was made along the coastline from Cape Fear to Cape Lookout, North Carolina. This

3 1⁄2 hour flight was spent examining wind damage along the coast and intercostal waterway area.

On Tuesday, July 16, no flight was scheduled as U.S. Geological Survey was flying on a storm

surge mission. A ground survey of agricultural damage was conducted in the afternoon from

Wilmington northward to just south of Warsaw, North Carolina.

Wednesday, July 17, a trip was made with the MIC and WCM of NWSO Wilmington to observe

the damage at Carolina Beach and Kure Beach, North Carolina. Both locations lost piers. There

were some structures with portions of roofs torn off, but most structures survived well. In the

afternoon, another flight was made with the Twin Otter. This flight concentrated on inland

damage from the hurricane. Damage was mainly confined to crops and trees and extended as far

north as Goldsboro, North Carolina.

Coastal Damage

Wind damage was visible from the air from just north of Bald Head Island near Cape Fear to

Atlantic Beach, south of Morehead City, North Carolina. The most intense damage with peak

wind gusts estimated at 110 mph was located between North Topsail Beach and Emerald Isle,

North Carolina. In this area, many beach homes suffered roof damage. The roof damage varied

from torn off shingles to whole roofs lost. There were very few total failures to structures due to

wind. Of those that did fail, it appears they were modular home or mobile home structures. 

Visible coastal erosion was found, especially to beach sand dunes and to a coastal road at North

Topsail Beach. However, the damage was not as severe as in other recent landfalling hurricanes,

such as Opal in 1995.

Further inland along the edge of the intercoastal waterway, the primary damage was to trees. 

Numerous trees fell with most falling in the area northeast of the eye from west of Surf City

northeastward to just east of Swansboro, North Carolina. This area extended northward to the
E-2

southern portions of Jacksonville. Wind gusts in this area were estimated to be between 80 and

100 mph.

Inland Agricultural Areas

Agricultural areas were particularly exposed to high winds from Hurricane Bertha. Much of the

damage was to corn and tobacco crops. Both of these crops are vulnerable to high wind gusts. 

Much of the agricultural damage was west of the eyewall rather than east. This is due in part to

much of the corn and tobacco crops being grown further west rather than along the eastern

coastal areas. The storm tracked slowly northward along the North Carolina and South Carolina

coastline before making landfall. Thus, crops were exposed to strong northeast winds for an

extended period of time, and this caused crops to weaken significantly. The agricultural damage

extended as far as 40 miles west of the eye and as far north as Goldsboro, North Carolina, which

is approximately 75 to 80 miles inland. Most of the damage occurred in unprotected (no blockage

by trees or buildings) areas along the edge of fields. Some fields had more widespread damage

where a streak of particularly high wind toppled several rows of corn or tobacco.

Tornadoes

The initial SPC log of tornadoes associated with Bertha indicated at least six touched down. 

Three of these reported tornadoes were investigated by air. There was no visible evidence of

tornado damage in the three locations of New Bern, Newport, and near Winnabow, North

Carolina. It is possible that some of these tornadoes either blended in with the hurricane damage

or were not visible from the air. East of Jacksonville, North Carolina, a tornado track was

identified from the air and was rated an F1 on the Fujita Tornado Intensity Scale (Appendix C)

with a path length of approximately 1 1⁄2 miles. The one area that a tornado most likely did not

occur was near Winnabow. 

Conclusions and Acknowledgments

The most severe wind damage associated with Hurricane Bertha was along the coast and east of

the eye center, typical of most hurricanes. The peak wind speeds estimated from the aerial survey

was 110 mph. Although damage to structures was minimal in this hurricane, agricultural damage

was extensive. 

The author would like to thank the AOC and their fine pilots, Lieutenants Pickett and

Longenecker. The author would also like to extend thanks to the Office of the Federal

Coordinator for their help in making this survey possible and to Richard Anthony and Tom

Matheson from the NWSO Wilmington, North Carolina, for their assistance in conducting the

survey.
B-1

Appendix B

Meteorological Tables