Service Change Notice

NOUS41 KWBC 171810
PNSWSH

SERVICE CHANGE NOTICE 08-20
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
210 PM EDT MON MAR 17 2008

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

FROM:       THERESE Z. PIERCE
              CHIEF...MARINE AND COASTAL SERVICES BRANCH

SUBJECT:    CHANGES TO TROPICAL CYCLONE PROBABILISTIC WIND   
            SPEED TEXT PRODUCTS: EFFECTIVE MAY 15 2008

REFER TO:   SERVICE CHANGE NOTICE /SCN/ 08-19: TRANSMITTED
            MAR 17 2008 

BASED ON USER FEEDBACK...SEVERAL ENHANCEMENTS TO THE TROPICAL 
CYCLONE PROBABILISTIC WIND SPEED TEXT /PWS/ PRODUCTS BECOME 
EFFECTIVE MAY 15 2008. THIS INCLUDES THE FOLLOWING SUITE OF  
PRODUCTS:   

BASIN                   WMO HEADING             AWIPS ID
ATLANTIC                FONT/11-15/ KNHC        PWSAT/1-5/
EASTERN PACIFIC         FOPZ/11-15/ KNHC        PWSEP/1-5/
CENTRAL PACIFIC         FOPA/11-15/ PHFO        PWSCP/1-5/

1.  A MAXIMUM WIND SPEED /INTENSITY/ PROBABILITY TABLE...DENOTED 
AS SECTION I...WILL BE ADDED. THE TABLE WILL PROVIDE 
PROBABILITIES THAT THE MAXIMUM SUSTAINED WIND SPEED OF THE 
TROPICAL CYCLONE WILL BE WITHIN ANY OF THE FOLLOWING CATEGORIES 
AT EACH OFFICIAL FORECAST TIME IN THE NEXT 5 DAYS:  
-DISSIPATED
-TROPICAL DEPRESSION
-TROPICAL STORM
-HURRICANE 
-EACH SAFFIR-SIMPSON HURRICANE SCALE CATEGORIES 1 THROUGH 5.

2.  THE EXISTING TABLE IN THE CURRENT PWS PRODUCTS WILL BE 
DENOTED AS SECTION II AND IDENTIFIED AS THE WIND SPEED 
PROBABILITY TABLE FOR SPECIFIC LOCATIONS.  ADDITIONALLY THE 
CURRENT LOCATION-SPECIFIC PROBABILITIES DO NOT INCLUDE LOCATIONS 
HAVING A CUMULATIVE 5-DAY PROBABILITY LESS THAN 2.5 PERCENT.  
THIS THRESHOLD WILL BE LOWERED TO 1.0 PERCENT FOR THE 64-KNOT 
PROBABILITIES ONLY.

3.  THE PORTION OF THE EXISTING PRODUCT...NOW DENOTED AS WIND 
SPEED PROBABILITIES FOR FORECAST POSITIONS...PROVIDING WIND SPEED 
PROBABILITIES AT THE OFFICIAL FORECAST POINTS THROUGH 120 
HOURS...WILL BE ELIMINATED. THIS INFORMATION IS REPLACED BY THE 
NEW TABLE IN SECTION I...PROVIDING MAXIMUM WIND SPEED 
PROBABILITIES FOR THE FULL AREAL EXTENT OF THE STORM THROUGH  
120 HOURS. 

AN EXAMPLE OF THE ENHANCED PWS TEXT PRODUCTS IS PROVIDED ONLINE 
AT /USE LOWER CASE LETTERS/:

        HTTP://WWW.WEATHER.GOV/OS/HURRICANE/PDFS/WIND-PROB.PDF

IF YOU HAVE ANY QUESTIONS...PLEASE CONTACT

        SCOTT KISER
        NATIONAL WEATHER SERVICE
        MARINE AND COASTAL SERVICES BRANCH
        1325 EAST WEST HWY ROOM 13126
        SILVER SPRING MARYLAND  20910
        PHONE: 301-713-1677 EXTENSION 121

NWS SERVICE CHANGE NOTICES ARE ONLINE AT /USE LOWER CASE/:

       HTTP://WWW.NWS.NOAA.GOV/OM/NOTIF.HTM

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