Technical Implementation Notice

NOUS41 KWBC 231211
PNSWSH

TECHNICAL IMPLEMENTATION NOTICE 06-71
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
810 AM EDT MON OCT 23 2006

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 JANUARY 18 2007 

EFFECTIVE JANUARY 18 2007 AT 0300 COORDINATED UNIVERSAL TIME 
/UTC/...THE TEMPORAL RESOLUTION OF TROPICAL CYCLONE PROBABILISTIC 
WIND SPEED FORECASTS WILL CHANGE FROM 12 HOURS TO 6 HOURS.

CURRENTLY NWS ROUTINELY DISSEMINATES TROPICAL CYCLONE 
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: 0300...0900...1500...AND 2100 UTC...AND  
IN CONJUNCTION WITH THE ISSUANCE OF SPECIAL TROPICAL CYCLONE 
ADVISORIES. THESE PRODUCTS CURRENTLY PROVIDE THE PROBABILITIES OF 
SUSTAINED WIND SPEED EXCEEDANCE FOR THREE THRESHOLDS: 34 KNOTS 
...50 KNOTS...AND 64 KNOTS...AT 12 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.  

THE WMO HEADERS AND ASSOCIATED FORECAST INTERVALS FOR THE 
EXISTING PRODUCTS ARE AS FOLLOWS:

LDGA98 KNHC              0 HOUR
LDGC98 KNHC             12 HOUR
LDGE98 KNHC             24 HOUR
LDGG98 KNHC             36 HOUR
LDGI98 KNHC             48 HOUR
LDGJ98 KNHC             60 HOUR
LDGK98 KNHC             72 HOUR
LDGL98 KNHC             84 HOUR
LDGM98 KNHC             96 HOUR
LDGN98 KNHC            108 HOUR
LDGO98 KNHC            120 HOUR

ON JANUARY 18 2007 AT 0300 UTC...THE TEMPORAL RESOLUTION OF THESE 
FORECAST PRODUCTS WILL CHANGE FROM 12 HOURS TO 6 HOURS. THE WMO 
HEADERS AND THE ASSOCIATED FORECAST INTERVALS FOR THE NEW SIX 
HOURLY PRODUCTS ARE LISTED BELOW. USERS WISHING TO RECEIVE THE 
NEW SIX HOURLY FORECAST PRODUCTS MUST MAKE THE FOLLOWING CHANGES 
TO THEIR DATABASES.

WMO HEADER      FORECAST INTERVAL               ACTION 
LDGB98 KNHC        6 HOURS                      ADD
LDGD98 KNHC        18 HOURS                     ADD
LDGF98 KHHC        30 HOURS                     ADD
LDGH98 KNHC        42 HOURS                     ADD
MDGM98 KNHC        54 HOURS                     ADD
MDGN98 KNHC        66 HOURS                     ADD
MDGT98 KNHC        78 HOURS                     ADD
MDGU98 KNHC        90 HOURS                     ADD
MDGV98 KNHC       102 HOURS                     ADD
MDGW98 KNHC       116 HOURS                     ADD

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

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

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

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

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