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Updated 1130 am Mon Sep 28 2009...corrected URL links

PUBLIC INFORMATION STATEMENT...COMMENT REQUEST 
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
240 PM EDT WED SEP 23 2009

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

FROM:    ELI JACKS
         CHIEF...FIRE AND PUBLIC WEATHER SERVICES BRANCH

SUBJECT: CURRENTLY SOLICITING COMMENTS BY NOVEMBER 30 2009
         REGARDING CHANGING THE MINIMUM HAIL SIZE CRITERION FOR
         ISSUING SEVERE THUNDERSTORM WARNINGS AND SEVERE
         WEATHER STATEMENTS

THE NWS IS CONSIDERING CHANGING THE MINIMUM HAIL SIZE CRITERION 
IT USES FOR ISSUING SEVERE THUNDERSTORM WARNING /SVR/ AND SEVERE 
WEATHER STATEMENT /SVS/ PRODUCTS FROM 3/4 INCH /PENNY/ DIAMETER 
OR LARGER TO 1 INCH /QUARTER/ DIAMETER OR LARGER.  NO CHANGE IS 
BEING PROPOSED TO THE SEVERE THUNDERSTORM WIND CRITERION: WIND 
GUSTS EQUAL TO OR IN EXCESS OF 50 KNOTS /58 MPH/.

COMMENTS REGARDING THIS PROPOSED CHANGE SHOULD BE BY NOVEMBER 30 
2009 TO:

http://www.weather.gov/survey/nws-survey.php?code=1incha-wr

WITH THE EXCEPTION OF CENTRAL AND WESTERN REGION WEATHER 
FORECAST OFFICES /WFO/... THE NWS CURRENTLY ISSUES SVR AND SVS 
PRODUCTS WHENEVER A THUNDERSTORM IS FORECAST TO CONTAIN HAIL 
SIZE 3/4 INCH /PENNY/ DIAMETER OR LARGER.

ON AN EXPERIMENTAL BASIS...CENTRAL AND WESTERN REGION WFOS ARE  
USING THE PROPOSED 1 INCH /QUARTER/ DIAMETER OR LARGER MINIMUM 
HAIL SIZE CRITERION TO ISSUE SVR AND SVS PRODUCTS UNTIL OCTOBER 
31 2009 AND NOVEMBER 30 2009... RESPECTIVELY.

PRODUCT DESCRIPTION DOCUMENTS /PDD/ FOR THESE EXPERIMENTAL 
PRODUCTS ARE AVAILABLE AT /USE LOWERCASE/:

http://products.weather.gov/viewliste.php

SERVICE CHANGE NOTICES /SCN/ ANNOUNCING THE CR AND WR 
EXPERIMENTAL PRODUCTS ARE ALSO ONLINE AT /USE LOWERCASE/:

http://www.nws.noaa.gov/om/notification/scn09-36wr_hail_exp.txt

AND

http://www.nws.noaa.gov/om/notification/scn09-19hail_change.txt

UPON THE COMPLETION OF THESE EXPERIMENTAL PERIODS AND THE CLOSE 
OF THIS PUBLIC INFORMATION STATEMENT /PNS/ COMMENT PERIOD...THE 
NWS WILL EVALUATE ALL RECEIVED COMMENTS TO DETERMINE WHETHER OR 
NOT TO PROCEED WITH THE SEVERE THUNDERSTORM MINIMUM HAIL SIZE 
CRITERION CHANGE.

IF THE PROPOSED SEVERE THUNDERSTORM MINIMUM HAIL SIZE CRITERION 
CHANGE IS APPROVED...ALL NWS WFOS IN THE CONTINENTAL UNITED 
STATES /CONUS/ AND OUTSIDE CONTINENTAL UNITED STATES /OCONUS/ 
WILL BEGIN ISSUING SVR AND SVS PRODUCTS FOR THUNDERSTORMS 
FORECAST TO CONTAIN MINIMUM HAIL SIZE 1 INCH /QUARTER/ DIAMETER 
OR LARGER AS SOON AS POSSIBLE AFTER TUESDAY JANUARY 5 2010.

A SERVICE CHANGE NOTICE WILL BE ISSUED WITH A MINIMUM 30 DAY 
ADVANCE LEAD TIME ANNOUNCING THIS CHANGE. 

IF YOU HAVE COMMENTS OR QUESTIONS REGARDING THIS PUBLIC 
INFORMATION STATEMENT...PLEASE CONTACT: 

  JOHN FERREE
  NATIONAL WEATHER SERVICE
  FIRE AND PUBLIC WEATHER BRANCH
  120 DAVID L. BOREN BLVD, SUITE 2312
  NORMAN OK 73072
  405-325-2209

john.ferree@noaa.gov

NATIONAL PUBLIC INFORMATION STATEMENTS ARE ONLINE AT /USE LOWERCASE/:

http://www.weather.gov/os/notif.htm