NOUS41 KWBC 181409 PNSWSH PUBLIC INFORMATION STATEMENT...SERVICE CHANGE NOTICE 03-39 NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC 1010 AM EDT FRI JUL 18 2003 TO FAMILY OF SERVICES /FOS/ SUBSCRIBERS...NOAA WEATHER WIRE SERVICE /NWWS/ SUBSCRIBERS...EMERGENCY MANAGERS WEATHER INFORMATION NETWORK /EMWIN/ SUBSCRIBERS... NOAAPORT SUBSCRIBERS...OTHER NATIONAL WEATHER SERVICE /NWS/ CUSTOMERS AND PARTNERS...AND NWS EMPLOYEES FROM GLENN AUSTIN ACTING CHIEF...FIRE AND PUBLIC WEATHER SERVICES BRANCH SUBJECT ZONE FORECAST PRODUCT MODIFIED FORMAT AND PHASED IMPLEMENTATION...EFFECTIVE BEGINNING OCTOBER 1 2003 ON WEDNESDAY OCTOBER 1 2003...AT 1800 UTC /COORDINATED UNIVERSAL TIME/...THE NATIONAL WEATHER SERVICE FORECAST OFFICES /WFO/ WILL IMPLEMENT A NEW DIRECTIVE...NWS INSTRUCTION 10-503...WFO PUBLIC WEATHER FORECAST PRODUCTS SPECIFICATION. THIS NEW DIRECTIVE SETS POLICY FOR AN IMPROVED ZONE FORECAST PRODUCT /ZFP/ IN A MODIFIED FORMAT. THE NEW ZFP FORMAT WILL BE IMPLEMENTED AT MOST CONTIGUOUS UNITED STATES /CONUS/ WFOS ON OCTOBER 1 2003. THE MODIFIED ZFP FORMAT WILL BE PHASED IN AT THE REMAINDER OF CONUS WFOS THROUGH DECEMBER 31 2003...AS NEW SOFTWARE BECOMES AVAILABLE AT THOSE LOCATIONS. OFF CONUS /OCONUS/ WFOS WILL ALSO BEGIN ISSUING THE ZFP IN THIS MODIFIED FORMAT AS SOFTWARE BECOMES AVAILABLE DURING 2004. THE IMPLEMENTATION SCHEDULE OF THE NEW ZFP FORMAT AT OCONUS WFOS WILL BE ANNOUNCED IN A FUTURE SERVICE CHANGE NOTICE. THIS NEW DIRECTIVE EXTENSIVELY CHANGES THE ZFP FORMAT. THE MOST SIGNIFICANT CHANGES ARE AS FOLLOWS: 1. THE DAY FOUR /4/ THROUGH DAY SEVEN /7/ 24-HOUR FORECASTS HAVE BEEN BROKEN INTO 12-HOUR SEGMENTS...RESULTING IN SEAMLESS 13 OR 14 PERIOD FORECASTS DEPENDING UPON THE ISSUANCE TIME. 2. THE TWO MANDATORY ZFP ISSUANCE TIME WINDOWS HAVE BEEN MODIFIED TO NO LATER THAN 4 AM AND 4 PM LOCAL TIME. 3. WIND FORECASTS ARE EXTENDED TO 60 HOURS. 4. THE DOT LESS THAN CODE /.