[nws-changes] [20090305: hail Fwd: ADMIN NOTICE NOUS41 KWBC]

• To: nws-changes@xxxxxxxxxxxxxxxx
• Subject: [nws-changes] [20090305: hail Fwd: ADMIN NOTICE NOUS41 KWBC]
• From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx>
• Date: Thu, 05 Mar 2009 14:10:41 -0700

-------- Original Message --------

307
NOUS41 KWBC 052036
PNSWSH

SERVICE CHANGE NOTICE 09-19
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
335 PM EST THU MAR 5 2009

TO:      SUBSCRIBERS:
         -FAMILY OF SERVICES
         -NOAA WEATHER WIRE SERVICE
         -EMERGENCY MANAGERS WEATHER INFORMATION NETWORK
         OTHER NWS PARTNERS...AND NWS EMPLOYEES

FROM:    KIM RUNK
         CHIEF...INTEGRATED SERVICES DIVISION
         CENTRAL REGION HEADQUARTERS KANSAS CITY MO

SUBJECT: EXPERIMENTAL CRITERION CHANGE FOR HAIL SIZE IN SEVERE
         THUNDERSTORM WARNING DETERMINATION AT ALL CENTRAL
         REGION WEATHER FORECAST OFFICES FROM THREE-QUARTER
         /0.75/ INCH TO ONE /1/ INCH IN DIAMETER OR LARGER
         EFFECTIVE BY OR BEFORE JULY 1 2009

IN A ROLL OUT IMPLEMENTATION FROM APRIL 1 THROUGH JULY 1 2009...
ALL CENTRAL REGION /CR/ WEATHER FORECAST OFFICES /WFOS/ WILL
BEGIN USING A NEW EXPERIMENTAL HAIL CRITERION FOR DETERMINING
WHEN TO ISSUE SEVERE THUNDERSTORM WARNINGS /SVR/. IN AN EFFORT
TO BETTER REPRESENT HAIL WHICH PRODUCES DAMAGE AND TO REDUCE
USER COMPLACENCY TO NUMEROUS SEVERE THUNDERSTORM WARNINGS FOR
THREE-QUARTER /0.75/ INCH DIAMETER HAIL...THE WFO/S IN CR
WILL USE HAIL CRITERION OF ONE /1/ INCH IN DIAMETER OR LARGER AS
OPPOSED TO THE REFERENCED /0.75/ INCH CRITERION.  THERE IS NO
CHANGE IN HAIL CRITERION FOR AVIATION THUNDERSTORM WARNINGS
/I.E. CONVECTIVE SIGMETS/ OR FOR SPECIAL MARINE WARNINGS /SMW/.

THIS EFFORT IS AN EXPANSION OF A SUCCESSFUL EXPERIMENT CONDUCTED
IN THE KANSAS OVER THE LAST 4 SEVERE WEATHER SEASONS WHERE WFOS
USED THE ONE /1/ INCH CRITERION FOR SEVERE THUNDERSTORM
WARNINGS. DUE TO THE OVERWHELMING POSITIVE RESPONSE TO THIS
CHANGE...THE ENTIRE CENTRAL REGION WILL TEST THE NEW
EXPERIMENTAL HAIL CRITERION WITH THE POTENTIAL FOR FURTHER
EXPANSION ACROSS NWS IN THE FUTURE.

A PRODUCT DESCRIPTION DOCUMENT /SDD/ FOR THIS EXPERIMENT IS
AVAILABLE ONLINE AT /USE LOWER CASE LETTERS/:

    HTTP://PRODUCTS.WEATHER.GOV/

A MAP SHOWING AFFECTED OFFICES IS ONLINE AT /USE LOWERCASE/:

HTTP://WWW.WEATHER.GOV/OS/NOTIFICATION/RESOURCES/CR_WFOS.PDF

NO CHANGE WILL OCCUR WITH RESPECT TO WIND SPEED AND SEVERE
THUNDERSTORM WARNINGS. WINDS EQUAL TO OR IN EXCESS OF 50 KNOTS
/58 MPH/ WILL REMAIN THE CRITERION.

FOR THUNDERSTORMS EXPECTED TO PRODUCE 3/4 INCH TO 7/8 INCH
DIAMETER HAIL BUT REMAIN BELOW SEVERE WIND LIMITS...WFOS MAY
ISSUE A SIGNIFICANT WEATHER ADVISORY USING THE SPECIAL WEATHER
STATEMENT /SPS/ PRODUCT OR THE SHORT TERM FORECAST /NOW/
PRODUCT. WFOS WILL ALSO CONTINUE TO COLLECT AND DISTRIBUTE HAIL
REPORTS THAT ARE THREE-QUARTERS /0.75/ INCH IN DIAMETER OR
GREATER BY WAY OF THE LOCAL STORM REPORT /LSR/ IN AS NEAR REAL
TIME AS POSSIBLE.

FOR QUESTIONS ON THIS SERVICE CHANGE NOTICE PLEASE CONTACT:

   KIM RUNK
   NATIONAL WEATHER SERVICE
   CENTRAL REGION HEADQUARTERS
   7220 NW 101ST TERRACE
   KANSAS CITY MO
   PHONE: 816-268-3140
   EMAIL: KIM.RUNK@xxxxxxxx

NATIONAL SERVICE CHANGE NOTICES ARE ONLINE AT /USE LOWERCASE/:

 HTTP://WWW.WEATHER.GOV/OS/NOTIF.HTM

$$