Technical Implementation Notice

NOUS41 KWBC 161219 
PNSWSH

TECHNICAL IMPLEMENTATION NOTICE 07-22
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
817 AM EDT MON APR 16 2007

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

SUBJECT:   CHANGES TO TROPICAL CYCLONE PROBABILISTIC WIND SPEED
           PRODUCTS: EFFECTIVE MAY 15 2007 

REF:       TIN 06-71 ANNOUNCING CHANGES TO THE TROPICAL CYCLONE         
           PROBABILISTIC WIND SPEED PRODUCTS: TRANSMITTED
           OCTOBER 23 2006

BEGINNING MAY 15 2007 THE NATIONAL HURRICANE CENTER /NHC/ WILL 
HAVE THE CAPABILITY TO ISSUE TROPICAL CYCLONE INCREMENTAL 
PROBABILISTIC WIND SPEED FORECASTS.

CURRENTLY THE NHC DISSEMINATES TROPICAL CYCLONE CUMULATIVE 
PROBABILISTIC WIND SPEED FORECASTS WHEN TROPICAL CYCLONES ARE 
FORECAST FOR THE ATLANTIC...THE EASTERN PACIFIC...CENTRAL 
PACIFIC...AND WESTERN PACIFIC HURRICANE BASINS.  THESE PRODUCTS 
ARE DISSEMINATED FOUR TIMES PER DAY WHEN TROPICAL CYCLONE 
ADVISORIES ARE ISSUED AT 0300...0900...1500...AND 2100 
COORDINATED UNIVERSAL TIME /UTC/...AND ALSO IN CONJUNCTION WITH 
THE ISSUANCE OF SPECIAL TROPICAL CYCLONE ADVISORIES. THESE 
PRODUCTS PROVIDE THE PROBABILITIES OF SUSTAINED WIND SPEED 
EXCEEDANCE FOR THREE THRESHOLDS:  34 KNOTS...50 KNOTS AND 64 
KNOTS...AT 6 HOURLY FORECAST INTERVALS OUT TO 120 HOURS.  THE 
PRODUCTS ARE ISSUED ON AWIPS GRID 231 IN GRIDDED BINARY /GRIB2/ 
FORMAT AT A 0.5 DEGREE KILOMETER RESOLUTION. 

FOR ADDITIONAL DETAILS ON THE PROBABILISTIC WINDS PRODUCTS...TO 
INCLUDE DEFINITIONS OF THE CUMULATIVE AND INCREMENTAL 
PROBABILITIES...REFER TO THE NHC WEB SITE AT /USE LOWER CASE 
LETTERS/:

     HTTP://WWW.NHC.NOAA.GOV/ABOUTNHCPROD.SHTML

THE INCREMENTAL DATA WILL BE ISSUED UNDER THE SAME HEADERS AS THE 
CUMULATIVE DATA. THERE ARE NO CHANGES TO THE COMMUNICATION 
HEADERS....REFERENCE TIN 06-71 TRANSMITTED ON OCTOBER 23 2006.  
THE GRIB FIELD DESCRIPTORS FOR THE INCREMENTAL DATA ARE DIFFERENT 
FROM THE CUMULATIVE DATA FIELD DESCRIPTORS.  

IF YOU HAVE QUESTIONS REGARDING THIS NOTICE...PLEASE CONTACT:

     SCOTT KISER
     NATIONAL WEATHER SERVICE
     MARINE AND COASTAL SERVICES BRANCH
     1325 EAST WEST HIGHWAY
     SILVER SPRING MARYLAND 20910
     EMAIL:  SCOTT.KISER@NOAA.GOV

THIS AND ALL OTHER NWS TECHNICAL IMPLEMENTATION NOTICES ARE 
POSTED AT /USE LOWER CASE LETTERS/:

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

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