# Presentation: 410912

***Tropical Weather Outlook***

***Hurricane Season 2007***
***Are You Ready?****** ***

**Hurricane Ivan before landfall...**

## Season Officially Begins June 1st 
Earliest Date of a Named Storm (Tropical Storm Ana)
April 20-24, 2003
Winds of 58 mph.
Ana was the first Atlantic tropical storm of record to form in April. It moved generally eastward across the central Atlantic.
Season Officially Ends November 30th 
Latest Date of a Named Storm (Tropical Storm Zeta 2005 and Hurricane Alice 1954)
Both Formed on December 30 as Tropical Storms
Alice wound up increasing to a Hurricane later in January 1955
Zeta remained a Tropical Storm through January 6 2006.

- Earliest Date of a Named Storm (Tropical Storm Ana)
- April 20-24, 2003
- Winds of 58 mph.
- Ana was the first Atlantic tropical storm of record to form in April. It moved generally eastward across the central Atlantic.
- Season Officially Ends November 30th
- Latest Date of a Named Storm (Tropical Storm Zeta 2005 and Hurricane Alice 1954)
- Both Formed on December 30 as Tropical Storms
- Alice wound up increasing to a Hurricane later in January 1955
- Zeta remained a Tropical Storm through January 6 2006.

## Normal Season 

- Average from 1950 – 2006
- 11 Named Storms
- 6 Hurricanes
- 2...become Major Hurricanes
- Category 3 or greater

## 1970-1994 vs. 1995-2006

- 1970 to 1994
- 8.6 Named Storms
- 3.6 of those named...become Hurricanes
- 1.5 of the Hurricanes...become Major Hurricanes (Category 3...4...or 5).
- 1995 to 2006
- 13 Named Storms
- 7.7 of those named...become Hurricanes
- 3.6 of the Hurricanes...become Major Hurricanes (Category 3...4...or 5)

## Why Have There Been So Many More Systems Since 1995?

## Reasons for Stark Differences

- First Type of Climate Pattern Used for Strength of
- 				Hurricane Season
- Atlantic Multi-Decadal Oscillation (25 to 40 year period of increased activity)
- Natural occurrence and has been documented for at least the last 150 years.
- Active Phase (1995-Present, 12th year)
- Produces lower wind shear (changing winds with height)
- 		- This wind shear was extremely low during June and July of 2005
- Produces warmer waters
- 	across the tropical Atlantic
- Produces conducive winds
- 	coming off the west coast of
- 	Africa.
- Non-Active Phase (1970-1994)
- Higher wind shear
- Cooler waters
- Weak flow off the African
- 	Coast.
- Active Phase (1950 to 1969)
- Several Category 5
- 	hurricanes were seen.

## Reasons for Stark Differences

- Second Type of Climate Pattern Used for Strength
- 				of a Hurricane Season
- ENSO (El Niño/Southern Oscillation)
- Also known as the (El Niño/ La Niña) cycle (Dr Gray of Colorado State discovered the cycle in 1984)
- El Niño - refers to a periodic warming of the ocean waters over the central equatorial Pacific. (SST of +0.5 above climate average.)
- Strong El Niño conditions will strengthen hurricane activity in the Pacific, while inhibiting Atlantic activity. Main reason is the change in wind shear and differences in water temperatures.
- La Niña - refers to a periodic cooling of those waters.
- Cooling of sea surface temperatures in the Central and Eastern Pacific with an observed SST of -0.5 below climatic average.
- La Niña conditions tend to develop in spring to early summer with greatest impacts later in the year.
- A La Niña usually last for a period of 1 to 3 years
- La Niña conditions can tend to favor hurricane development in the Atlantic due to lack of shear
- 		Strong La Niña conditions will inhibit activity in the Pacific and 	strengthen activity in the Atlantic. Oceans are cyclical so when one 	waterway is cool another one would show the reverse trend.
- According to the latest trends according to NOAA, and using data since 1950, the observed breakdown of the previous El Niño in 2006-2007 shows the strongest SST cooling on record.
- We are already in an ENSO Neutral pattern with models predicting a La Niña cycle with the next 1 to 3 months.

## The Tropics During La Niña

- 1950 through 2001
- 14 tropical systems have impacted central Alabama
- 3 Summer storms
- 2 were late August into September; 1 in July
- 11 Autumn storms (Sep – Nov)

## Other Influences on a Hurricane Season?

## Other Influences

- Sea Surface Temperatures (SST)
-  (Generally >80 Degrees)
- The warmer the water the more “Fuel” for the hurricane to develop in.
- The higher the temperature...the more “fuel” for the production.
- The SST can also lead to lower sea level pressure.
- Type of Climate Pattern
- Atlantic Multi-Decadal Oscillation
- ENSO (El Niño/Southern Oscillation)
- El Niño / La Niña Cycle
- Madden-Julian Oscillation
- The MJO is a naturally occurring component of our coupled ocean-atmosphere system and the typical length of the MJO cycle or wave is approximately 30-60 days
- Tropical Rainfall Periods that influence temperatures and clouds in the Inter Tropical Convergence Zone (favorable for Hurricane Production)
- Strong MJO patterns are usually associated with ENSO-Neutral or weak La Niña cycles.
- Limiting Factors
- Wind fields coming off the coast of Africa....Saharan Air Layer (SAL).
- Develop easterly winds in the Inter-Tropical Convergence Zone (ITCZ)
**These winds bring in dry air from the Saharan Desert. **
**The drier air would hinder the development of Cape Verde storms.**
**2006 was a prime example as dust storms moved off the African coast and inhibited development of Cape Verde systems. (Although there was a developing El Nino as well.)**

## 2007:What is Expected?

## Why:Influences for 2007

- Climate Factors
- Atlantic Tropical Multi-Decadal Oscillation
- We are currently in the ACTIVE PHASE. (12th year of a 25 – 40 year cycle)
- La Niña Conditions
- As of May 22 2007, a neutral pattern was in place.
- However, the pattern is on the cool side, with several areas near the -0.5 criteria for a La Niña.
- To be classified as a full fledged La Niña, there needs to 5 consecutive months at or below criteria.
- The 2006/07 El Niño dissipated earlier than normal, allowing time for a La Niña to begin developing during the preferred March to June period
- A large area of cold sub-surface water is persisting in the central to eastern tropical Pacific Ocean
- By July 2007, La Nina conditions are probable, with the biggest impact occurring around the September time-period.
- La Nina typically means higher than normal activity in the Atlantic Basin.
- Madden-Julian Oscillation
- As of May 14 2007, an incoherent pattern is in place.
- This pattern is expected to remain this way leading up to the very first of the hurricane season.
- Based on past studies, the MJO is expected to be STRONG this summer, enhancing thunderstorm activity in the tropics.
- Sea-Surface Temperatures (SST)
- On a whole current Atlantic SST’s are 0.6 degrees C (1 degree F) above normal.
- SST’s in the Gulf are 78 to 82 degrees F.
- SST’s in the in the Caribbean are 81 to 85 degrees F.
- SST’s in the Atlantic are 80 degrees F or less north of the Bahamas.
- These temperatures will continue to increase as the warmer seasons come.

## Predictions for 2007

| Predictions | Named Storms | Hurricanes | Major
(Cat. 3 or Greater)
Hurricanes | Probability of major hurricane
landfall along Gulf Coast |
| --- | --- | --- | --- | --- |
| NHC | 13-17  | 7-10  |  3-5 |   |
| Dr Gray | 17 | 9 | 5 | 49 Percent Chance (above average) |
| Average since 1950 for a “Below Normal Year” | 6.9 | 3.7 | 1.1 |  |
| Average since 1950 for a “Above Normal Year” | 13.7 | 8.6 | 4.5 |  |
|  Average since 1950  | 11 | 6 | 2 | 30 Percent Chance |

- NHC is forecasting a 75% chance of an Above Average Season

## Hurricane Scale

| The Saffir-Simpson Hurricane Scale |  |  |  |
| --- | --- | --- | --- |
|   | Winds | Pressure | Example for Alabama at Landfall |
| TropicalDepression | 30-38 mph |   |   |
| Tropical Storm | 39-73 mph |   | Arlene |
| Category 1 | 74-95 mph | >979 mb | Danny |
| Category 2 | 96-110 mph | 965-979 mb | Georges |
| Category 3 | 111-130 mph | 945-964 mb | Frederic / Katrina / 
Ivan / Opal |
| Category 4 | 131-155 mph | 920-944 mb | Charley (FL) |
| Category 5 | greater than 155 mph  | <920 mb | Camille |

## 2007: A Look Ahead:Tropical Storm and Hurricane Names for 2007

|  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- |
|  |  |  |  |  |  |
|   | Name | Pronunciation |   | Name | Pronunciation |
| 1 | Subtropical Storm Andrea |   | 12 | Lorenzo |   |
| 2 | Barry |   | 13 | Melissa |   |
| 3 | Chantal | shan-TAHL | 14 | Noel |   |
| 4 | Dean |   | 15 | Olga |   |
| 5 | Erin | AIR-in | 16 | Pablo | PA-blow |
| 6 | Felix | FEEL-ix | 17 | Rebekah |   |
| 7 | Gabrielle | ga-bree-EL | 18 | Sebastien | say-BAS-tyan |
| 8 | Humberto | oom-BAIR-to | 19 | Tanya | TAHN-ya |
| 9 | Ingrid |   | 20 | Van |   |
| 10 | Jerry |   | 21 | Wendy |   |
| 11 | Karen |   | *** |  If all names are used go to  | The Greek List |

|   | Name |   | Name |
| --- | --- | --- | --- |
| 22 | Alpha | 34 | Nu |
| 23 | Beta | 35 | Xi |
| 24 | Gamma | 36 | Omicron |
| 25 | Delta | 37 | Pi |
| 26 | Epsilon | 38 | Rho |
| 27 | Zeta | 39 | Sigma |
| 28 | Eta | 40 | Tau |
| 29 | Theta | 41 | Upsilon |
| 30 | Lota | 42 | Phi |
| 31 | Kappa | 43 | Chi |
| 32 | Lambda | 44 | Psi |
| 33 | Mu | 45 | Omega |

## What are the Most Well Known Hurricanes to Impact Alabama Since 1969?

**Hurricane Camille**

**Hurricane Katrina**

## Hurricane Camille (August 17, 1969) Retired
Category 5 at landfall in MS (Second lowest pressure at landfall)
Highest Winds: 190 mph along the coastline
Heaviest Rain: Heaviest along SW Alabama
Hurricane Eloise (September 23, 1975) Retired
Category 3 at landfall (Only Hurricane to hit the US in 1975)
Highest Winds: 120 mph in Ozark (Lee County)
Heaviest Rain: 5 to 7 inches central and southern Alabama
Hurricane Frederic (September 12-13, 1979) Retired
Category 4 at strongest: Category 3 at landfall
Highest Winds: 125 mph across Dauphin Island (Mobile County)
Heaviest Rain: 7 to 10 inches across Mobile County
Hurricane Elena (September 2-3, 1985) Retired
Category 3 at landfall in SE Mississippi
Highest Winds: 100 mph across Dauphin Island (Mobile County)
Heaviest Rain: 1 to 3 inches across Mobile County
Hurricane Juan (October 30-November 1, 1985)
	This hurricane was not retired but the name was retired later
Category 1 with landfall in LA: Tropical Storm with landfall in SW AL/FL (Latest date of an impact to Alabama)
Highest Winds: 60 mph along the AL Coast
Heaviest Rain: 5 to 10 inches across southern Alabama

- Category 5 at landfall in MS (Second lowest pressure at landfall)
- Highest Winds: 190 mph along the coastline
- Heaviest Rain: Heaviest along SW Alabama
- Hurricane Eloise (September 23, 1975) Retired
- Category 3 at landfall (Only Hurricane to hit the US in 1975)
- Highest Winds: 120 mph in Ozark (Lee County)
- Heaviest Rain: 5 to 7 inches central and southern Alabama
- Hurricane Frederic (September 12-13, 1979) Retired
- Category 4 at strongest: Category 3 at landfall
- Highest Winds: 125 mph across Dauphin Island (Mobile County)
- Heaviest Rain: 7 to 10 inches across Mobile County
- Hurricane Elena (September 2-3, 1985) Retired
- Category 3 at landfall in SE Mississippi
- Highest Winds: 100 mph across Dauphin Island (Mobile County)
- Heaviest Rain: 1 to 3 inches across Mobile County
- Hurricane Juan (October 30-November 1, 1985)
- 	This hurricane was not retired but the name was retired later
- Category 1 with landfall in LA: Tropical Storm with landfall in SW AL/FL (Latest date of an impact to Alabama)
- Highest Winds: 60 mph along the AL Coast
- Heaviest Rain: 5 to 10 inches across southern Alabama

**Hurricanes from 1969 to 1994**

**Hurricane Frederic**

**Hurricane Camille**

**Hurricane Elena**

**Hurricane Juan’s Track**

## Hurricane Erin (August 2-4, 1995) 
Category 2
Highest Winds: 60 mph across southern Alabama
Heaviest Rain: 7 inches across southwest Alabama
Hurricane Opal (October 4-5, 1995) Retired
Category 4 at strongest: Category 3 at landfall
Highest Winds in Central Alabama: 90 mph in Montgomery (Montgomery County)
Highest Winds in Alabama:95 mph at Fort Rucker (Dale County)
Heaviest Rain in Central Alabama: 6.30 inches in Clanton (Chilton County)
Heaviest Rain in Alabama: 8.10 inches in Evergreen (Conecuh County)
Hurricane Danny (July 18-23, 1997) 
Category 4 at strongest: Category 1 at landfall (Stalled out in Mobile Bay)
# of Tornadoes: 1 F0 in Central Alabama
Highest Winds: 70 mph across southwestern Alabama
Heaviest Rain: 43 inches on Dauphin Island in Mobile County
Hurricane Georges (September 28-29,1998) Retired
Category 4 at strongest: Category 2 at landfall
# of Tornadoes: 8 Total (8 F0’s) in Central Alabama
Highest Winds: 70 mph in southwest Alabama
Heaviest Rain in Central Alabama: 9.14 inches at Brundidge (Pike County)
Heaviest Rain in Alabama: 29.66 inches at Bay Minette (Baldwin County)
Hurricane Isidore (September 25-27, 2002) Retired
Category 3 at strongest: Tropical Storm at US Landfall
Highest Winds: 48 mph at Red Mountain (Jefferson)
Heaviest Rain: 5.27 inches at Wright (Lauderdale)
Hurricane Ivan (September 16-17, 2004) Retired
Category 4 at strongest: Category 3 at landfall
# of Tornadoes: 6 Total (6 F0’s) in Central Alabama
Highest Winds in Central Alabama: 90 mph in Demopolis (Marengo County)
Highest Winds in Alabama: 121 mph Gulf Shores (Baldwin County)
Heaviest Rain in Central Alabama: 9.81 inches in Birmingham (Jefferson County)
Heaviest Rain in Alabama: 11.66 inches at Millers Ferry (Wilcox County)

- Category 2
- Highest Winds: 60 mph across southern Alabama
- Heaviest Rain: 7 inches across southwest Alabama
- Hurricane Opal (October 4-5, 1995) Retired
- Category 4 at strongest: Category 3 at landfall
- Highest Winds in Central Alabama: 90 mph in Montgomery (Montgomery County)
- Highest Winds in Alabama:95 mph at Fort Rucker (Dale County)
- Heaviest Rain in Central Alabama: 6.30 inches in Clanton (Chilton County)
- Heaviest Rain in Alabama: 8.10 inches in Evergreen (Conecuh County)
- Hurricane Danny (July 18-23, 1997)
- Category 4 at strongest: Category 1 at landfall (Stalled out in Mobile Bay)
- # of Tornadoes: 1 F0 in Central Alabama
- Highest Winds: 70 mph across southwestern Alabama
- Heaviest Rain: 43 inches on Dauphin Island in Mobile County
- Hurricane Georges (September 28-29,1998) Retired
- Category 4 at strongest: Category 2 at landfall
- # of Tornadoes: 8 Total (8 F0’s) in Central Alabama
- Highest Winds: 70 mph in southwest Alabama
- Heaviest Rain in Central Alabama: 9.14 inches at Brundidge (Pike County)
- Heaviest Rain in Alabama: 29.66 inches at Bay Minette (Baldwin County)
- Hurricane Isidore (September 25-27, 2002) Retired
- Category 3 at strongest: Tropical Storm at US Landfall
- Highest Winds: 48 mph at Red Mountain (Jefferson)
- Heaviest Rain: 5.27 inches at Wright (Lauderdale)
- Hurricane Ivan (September 16-17, 2004) Retired
- Category 4 at strongest: Category 3 at landfall
- # of Tornadoes: 6 Total (6 F0’s) in Central Alabama
- Highest Winds in Central Alabama: 90 mph in Demopolis (Marengo County)
- Highest Winds in Alabama: 121 mph Gulf Shores (Baldwin County)
- Heaviest Rain in Central Alabama: 9.81 inches in Birmingham (Jefferson County)
- Heaviest Rain in Alabama: 11.66 inches at Millers Ferry (Wilcox County)

**Hurricanes from 1995 to 2004**

**Hurricane Danny**

**Hurricane Erin**

**Hurricane Isidore**

**Hurricane Opal**

** ****Hurricane Georges**

**Hurricane Ivan**

## Tropical Storm Arlene (June 11-12, 2005)
Tropical Storm
Highest Winds: 40 mph at Tuscaloosa (Tuscaloosa County)
Heaviest Rain: 4.60 inches at Newbern (Hale County)
Hurricane Cindy (July 6, 2005)
Category 1
# of Tornadoes: 8 Total (6 F0’s and 2 F1’s) in Central Alabama
Highest Winds: 29 mph at Tuscaloosa (Tuscaloosa County)
Heaviest Rain: 5.01 inches at Tallassee (Elmore County)
Hurricane Dennis (July 10-11, 2005) Retired
Category 4 at strongest: Category 3 Landfall
Highest Winds: 52 mph at Montgomery (Montgomery County)
Heaviest Rain: 8.63 inches at Sylvan Springs (Jefferson County) 
Hurricane Katrina (August 29-30, 2005) Retired
Category 5 at strongest: Category 3 at landfall
# of Tornadoes: 4 Total (2 F0’s and 2 F1’s) in Central Alabama
Highest Winds: 80 mph at Cuba (Sumter County)
Heaviest Rain: 4.82 inches at Hamilton (Marion County)
Hurricane Rita (September 25, 2005) Retired
Category 5 at strongest: Category 3 at landfall
# of Tornadoes: 21 Total (13 F0’s and 8 F1’s) in Central Alabama
Highest Winds: 40 mph at Montgomery (Montgomery County)
Heaviest Rain: 4.37 inches at Helena (Shelby County)

- Tropical Storm
- Highest Winds: 40 mph at Tuscaloosa (Tuscaloosa County)
- Heaviest Rain: 4.60 inches at Newbern (Hale County)
- Hurricane Cindy (July 6, 2005)
- Category 1
- # of Tornadoes: 8 Total (6 F0’s and 2 F1’s) in Central Alabama
- Highest Winds: 29 mph at Tuscaloosa (Tuscaloosa County)
- Heaviest Rain: 5.01 inches at Tallassee (Elmore County)
- Hurricane Dennis (July 10-11, 2005) Retired
- Category 4 at strongest: Category 3 Landfall
- Highest Winds: 52 mph at Montgomery (Montgomery County)
- Heaviest Rain: 8.63 inches at Sylvan Springs (Jefferson County)
- Hurricane Katrina (August 29-30, 2005) Retired
- Category 5 at strongest: Category 3 at landfall
- # of Tornadoes: 4 Total (2 F0’s and 2 F1’s) in Central Alabama
- Highest Winds: 80 mph at Cuba (Sumter County)
- Heaviest Rain: 4.82 inches at Hamilton (Marion County)
- Hurricane Rita (September 25, 2005) Retired
- Category 5 at strongest: Category 3 at landfall
- # of Tornadoes: 21 Total (13 F0’s and 8 F1’s) in Central Alabama
- Highest Winds: 40 mph at Montgomery (Montgomery County)
- Heaviest Rain: 4.37 inches at Helena (Shelby County)

**2005: One for the Record Books**
**Impacts Across Central Alabama**

## Quick Facts

- Top Ten Lowest Pressure Hurricanes
- 	through 2006
- 4 of the top	10 impacted
- 	Alabama
**(Highlighted in red)**** **
- 4 of the top 10
- 	occurred in the
-  	2004 and 2005
- 	included the
- 	lowest of all-time
- 	(Wilma, 2005)

| Lowest Pressure for a Hurricane through 2006 |  |  |  |
| --- | --- | --- | --- |
| Rank | Hurricane | Season | Min. pressure |
| 1 | Wilma | 2005 | 882 mb (hPa) |
| 2 | Gilbert | 1988 | 888 mb (hPa) |
| 3 | "Labor Day" | 1935 | 892 mb (hPa) |
| 4 | Rita | 2005 | 895 mb (hPa) |
| 5 | Allen | 1980 | 899 mb (hPa) |
| 6 | Katrina | 2005 | 902 mb (hPa) |
| 7 | Camille | 1969 | 905 mb (hPa) |
| 7 | Mitch | 1998 | 905 mb (hPa) |
| 9 | Ivan | 2004 | 910 mb (hPa) |
| 10 | Janet | 1955 | 914 mb (hPa |

## Quick Facts (Gulf of Mexico)

|   | Hurricane | Value |
| --- | --- | --- |
| Lowest Pressure
in the Gulf of Mexico | Wilma (2005) | 882 mb |
| Lowest Pressure
recorded at landfall | Camille (1969) | 909 mb |
| Highest Winds
recorded at landfall
As well as in the Gulf of
Mexico |  | Sustained 190 mph 
Gusts 220 mph
(Measured by Recon Plane) |

## Be Prepared

- Stay tuned to the changing weather (through television...radio...internet...or NOAA Weather Radio)
- Inland tropical systems have a tendency to produce tornadoes...strong winds...as well as flooding rains.
- Develop an Emergency Supply Kit
- This can be used year round with severe weather as well.
- Make sure you have plenty of batteries for flashlights.
- Develop a Family Disaster Plan
- Know what to do and when to do it.
- Websites to visit
**http://www.nhc.noaa.gov**
**http://www.cpc.ncep.noaa.gov**
**http://www.weather.gov/glossary**
**http://www.srh.noaa.gov/bmx**
**http://hurricane.atmos.colostate.edu/Forecasts/**
**http://www.nhc.noaa.gov/HAW2/english/intro.shtml (Hurricane Preparedness)**