# Presentation: 639059

- John Ferree
-  Severe Storms Services Leader
- NOAA National Weather Service
- Partner’s Meeting, June 18, 2008

**National Weather Service**

**Storm-Based Warnings**

## Outline

- Storm-Based Warnings Overview
- Active Year - How are we doing?
- Improving Severe Storms Services

- US Weather Bureau
- Tornado Warnings~1960

- Storm-Based
- WarningsOct. 1, 2007

- First Tornado Warning1948

- Polygonsadded1998

- NOAA Weather Radio (NWR) 1975

- NWR S.A.M.EFIPS Codes
- 1988

- S.A.M.EStandard
- 2003

## Storm-Based WarningsImplemented October 1, 2007

**County-Based Tornado Warnings**
**8 Counties under warning**
**Almost 1 million people warned**

** ****More specific**
** ****Increased clarity**
** ****Supports new****dissemination technology**

- Storm-Based WarningsImplemented October 1, 2007

**Three simultaneous tornadoes within line of severe thunderstorms  **

**Storm-Based Tornado Warnings**
**70% less area covered**
**~600,000 fewer people warned**

**Notes:**
This slide may seem familiar as it was used to introduce Storm-Based warnings at last year’s AMS/Partner’s Meeting. I only display it now to focus in on the goal of reducing falsely alarmed area. Since any particular community will be under warning less on average in the new storm-based system, the hope is that over time, confidence in NWS warnings will increase, and those under warning will be more likely to take action. We are now three and half months into the new implementation. Quite a bit of activity in October, and this month has been a January for the record books as far as severe weather (tornadoes in Wisconsin and Washington). So how are we doing so far?

## Storm-Based WarningsHow are we doing so far?

- Lot of ways to measure success
- Probability of Detection (Accuracy)
- Lead Time
- False Alarm Rate
- Reduction in False Alarm Area
- Qualitative Assessment

**Notes:**
There are the historical metrics of POD, LT, FAR. We also want to measure the reduction in false alarm area to be able to gage our success. We can also take an over all look at the warning polygons on an event by event basis. 

## County Area RatioPolygon size to County Size

- County Area RatioPolygon size to County Size

- Compliments of Daryl Herzmann at Iowa Environmental Mesonet

**Notes:**
This map depicts the ratio of polygon size to the size of the counties within the warning. Green areas are where the warning polygons are much smaller than counties/parishes. The red areas are where the warning polygons are close to the size of the polygons. As expected the greatest impact of this new service has been in areas where counties are large in the High Plains and West. The reduction in area warned is less in areas where counties/parishes are small in the Central and Eastern U.S. 

This metric is also driven by the weather. This winter there have been a lot of larger polygons with lines of storms associated with cold frontal activity. 

## 2008 – A lot of tornados

## 2008 - Now at 110 tornado fatalitiesmost since 1998  

- Super Tuesday Outbreak – Feb 5/6
- 56 Fatalities, 391 Injuries, $0.5 Billion in damages
- Mother’s Day Outbreak  - May 10/11
- EF4 Picher, OK to Neosho MO
- Memorial Day Weekend Outbreak

## Storm-Based Warning Issues

- Large polygons
- Less than 1% of Severe Thunderstorm Warnings
- Large threat areas
- Warnings with too much text
- Related to large polygons
- Odd shaped polygons
- Land/Marine interfaces
- County Warning Areaboundaries

- Tornado Warning Polygonand Velocity Couplet
- Little Sioux CampgroundJune 11, 2008

## Large Polygons – Long Text

-  Remove this includes the city of
-  Limit to 12 counties/parishes
-  New format (2+ yrs away)

## Too much text 

- Too much text

- Takes time to compose and transmit
- Impact of Call-To-Action statements minimized by length
- Add Call-To-Action marker

- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE MOBILE AL 211 PM CST SUN FEB 17 2008 THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A * TORNADO WARNING FOR...  SOUTHEASTERN CRENSHAW COUNTY IN SOUTH CENTRAL ALABAMA... * UNTIL 230 PM CST * AT 207 PM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR BULLUCK...  OR ABOUT 11 MILES SOUTH OF LUVERNE...MOVING NORTHEAST AT 50 MPH. * THE POSSIBLE TORNADO WILL OTHERWISE IMPACT MAINLY RURAL AREAS OF  THE SOUTHEASTERN CRENSHAW COUNTY. THIS IS SERIOUS.  NUMEROUS DAMAGE REPORTS CONTINUE TO FLOW INTO THE NWES OFFICE IN MOBILE ALABAMA.  TAKE COVER NOW! THE SAFEST PLACE TO BE DURING A TORNADO IS ON THE LOWEST FLOOR OF A STURDY BUILDING...PREFERABLY IN AN INTERIOR HALLWAY OR A ROOM SUCH AS A CLOSET OR BATHROOM. IF POSSIBLE...GET UNDER A WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. USE BLANKETS OR PILLOWS TO COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS. IN ADDITION TO THE TORNADO...THIS STORM IS CAPABLE OF PRODUCING LARGE DAMAGING HAIL OR DAMAGING STRAIGHT LINE WINDS. IF YOU ARE IN MOBILE HOME...EVACUATE IT AND GET ON THE LOWEST FLOOR OF A NEARBY STURDY BUILDING OR IN AN UNDERGROUND STORM SHELTER. IF NO SUBSTANTIAL SHELTER IS AVAILABLE AND A TORNADO IS FAST APPROACHING... SEEK SHELTER IN A CULVERT...DITCH OR LOW DEPRESSION AND COVER YOUR HEAD WITH YOUR HANDS. HEAVY RAINFALL MAY BE OBSCURING THIS TORNADO. TAKE COVER NOW! IF YOU WAIT TO SEE OR HEAR IT COMING...IT MAY BE TOO LATE TO GET TO A SAFE PLACE. DO NOT USE YOUR VEHICLE TO TRY TO OUTRUN AN APPROACHING TORNADO. ANY SIZE OF VEHICLE CAN BE EASILY BE TOSSED AROUND BY TORNADIC WINDS. IF YOU ARE CAUGHT IN THE PATH OF A TORNADO...LEAVE THE VEHICLE AND SEEK SHELTER IN A STRONG BUILDING. IF NO SAFE STRUCTURE IS AVAILABLE... SEEK SHELTER IN A CULVERT...DITCH OR LOW DEPRESSION AND COVER YOUR HEAD WITH YOUR HANDS. DO NOT USE HIGHWAY OVERPASSES FOR SHELTER. OVERPASSES DO NOT PROVIDE PROTECTION FROM TORNADIC WINDS. A TORNADO WATCH REMAINS IN EFFECT UNTIL 800     PM CST SUNDAY EVENING FOR SOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA.

- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE MOBILE AL 211 PM CST SUN FEB 17 2008 THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A * TORNADO WARNING FOR...  SOUTHEASTERN CRENSHAW COUNTY IN SOUTH CENTRAL ALABAMA... * UNTIL 230 PM CST * AT 207 PM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR BULLUCK...  OR ABOUT 11 MILES SOUTH OF LUVERNE...MOVING NORTHEAST AT 50 MPH. * THE POSSIBLE TORNADO WILL OTHERWISE IMPACT MAINLY RURAL AREAS OF  THE SOUTHEASTERN CRENSHAW COUNTY. THIS IS SERIOUS.  NUMEROUS DAMAGE REPORTS CONTINUE TO FLOW INTO THE NWES OFFICE IN MOBILE ALABAMA.  TAKE COVER NOW! THE SAFEST PLACE TO BE DURING A TORNADO IS ON THE LOWEST FLOOR OF A STURDY BUILDING...PREFERABLY IN AN INTERIOR HALLWAY OR A ROOM SUCH AS A CLOSET OR BATHROOM. IF POSSIBLE...GET UNDER A WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. USE BLANKETS OR PILLOWS TO COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS. A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM CST SUNDAY EVENING FORSOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA.

- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE MOBILE AL 211 PM CST SUN FEB 17 2008 THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A * TORNADO WARNING FOR...  SOUTHEASTERN CRENSHAW COUNTY IN SOUTH CENTRAL ALABAMA... * UNTIL 230 PM CST * AT 207 PM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO NEAR BULLUCK...  OR ABOUT 11 MILES SOUTH OF LUVERNE...MOVING NORTHEAST AT 50 MPH. * THE POSSIBLE TORNADO WILL OTHERWISE IMPACT MAINLY RURAL AREAS OF  THE SOUTHEASTERN CRENSHAW COUNTY. **PRECAUTIONARY/PREPAREDNESS ACTIONS. . .**
- THIS IS SERIOUS.  NUMEROUS DAMAGE REPORTS CONTINUE TO FLOW INTO THE NWES OFFICE IN MOBILE ALABAMA.  TAKE COVER NOW! THE SAFEST PLACE TO BE DURING A TORNADO IS ON THE LOWEST FLOOR OF A STURDY BUILDING...PREFERABLY IN AN INTERIOR HALLWAY OR A ROOM SUCH AS A CLOSET OR BATHROOM. IF POSSIBLE...GET UNDER A WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. USE BLANKETS OR PILLOWS TO COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS. A TORNADO WATCH REMAINS IN EFFECT UNTIL 800 PM CST SUNDAY EVENING FORSOUTHWESTERN ALABAMA AND NORTHWEST FLORIDA.
**&&**

## Odd shaped polygons

- Land/Marine boundary
- County Warning Area Boundary
- Editing out small portions of counties
- Errors – No QC

## Two other issues of interest

- Use of “Tornado Emergency” headline
- Watch extensions in time and area

- Vehicle in Picher OklahomaMay 10, 2008

- Hook Echo – Super Resolution WSR-88DTwo TornadoesMay 26, 2008

## Tornado Emergency

- First used on May 3, 1999
- Moore / Oklahoma City F5
- Used ~ 6 times/year since 1999
- No policy

**In exceedingly rare situations, when a severe threat to human life and catastrophic damage from a tornado is imminent or ongoing, the forecaster may insert the headline "...TORNADO EMERGENCY FOR [GEOGRAPHIC AREA]...". Additionally, in such a situation, this headline should only be used when reliable sources confirm a tornado, or there is clear radar evidence of the existence of a damaging tornado such as the observation of debris.**

- Proposed Wording for NWSI 10-511

## Watch extensions in time and area

- Complex system
- Extensions in time must be coordinated
- One watch
- All counties notcancelled are extended
- Extensions in areaonly available toWFO’s alreadyin the watch
- Forecaster Training

## Status of Storm Based Warnings

- Performance exceeding expectations
- A very active year
- Several issues
- Large Warnings
- Too Much Text
- Odd Shaped Polygons
- Policy for “Tornado Emergency”
- Watch-By-County issues
- Extensions in time
- Extensions in area

## Contact Information

- John.T.Ferree@noaa.gov
- 405-325-2209

- John Ferree
- 120 David L. Boren Blvd.
- Suite 2312
- Norman, OK 73072

## Proposed Dissemination Workshop

- Goal
- Partner input on new warning formats
- CAP, Grid, GIS, others
- When
- 1PM on Nov. 5, 2008 through 5PM on Nov. 6. 2008
- Where
- Norman, OK
- Silver Spring, MD
- Other?