NOUS41 KWBC 241304
PNSWSH

TECHNICAL IMPLEMENTATION NOTICE 09-25
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
905 AM EDT MON AUG 24 2009

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

FROM:     JASON TUELL
          SCIENCE PLANS BRANCH CHIEF
          OFFICE OF SCIENCE AND TECHNOLOGY 

SUBJECT:  GLOBAL FORECAST SYSTEM BUFR PRODUCT CHANGE:     
          EFFECTIVE AUGUST 25 2009

EFFECTIVE AUGUST 25 2009...BEGINNING WITH THE 1200 COORDINATED 
UNIVERSAL TIME /UTC/ RUN...THE NATIONAL CENTERS FOR ENVIRONMENTAL 
PREDICTION /NCEP/ WILL CORRECT AN ERROR IN THE BUFR SOUNDING 
OUTPUT FROM THE GLOBAL FORECAST SYSTEM /GFS/.  THIS ERROR IN THE 
VERTICAL INTERPOLATION OF TEMPERATURE HAS RESULTED IN 
TEMPERATURES AS MUCH AS 2 TO 3 DEGREES TOO COLD IN HIGH TERRAIN.  

THE AFFECTED BUFR PRODUCTS ARE AVAILABLE ON NOAAPORT UNDER 
THE HEADERS LISTED IN TABLE 1 BELOW AND ON THE NCEP AND NWS FTP 
SERVERS IN THE FOLLOWING LOCATIONS /WHERE YYYY IS THE YEAR...MM 
IS THE MONTH...DD IS THE DAY AND XX IS THE MODEL CYCLE.../ 
/USE LOWERCASE EXCEPT FOR SL...ST...MT... CY...RD...PT AND DF/:

FTP://FTP.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PROD/GFS.YYYYMMDDXX
/BUFR.TXXZ
ftp://tgftp.nws.noaa.gov/sl.us008001/st.opnl/mt.gfs_cy.xx/rd.yyyy
mmdd/pt.sndn_df.buf/
TABLE 1.  WMO COMMUNICATION IDENTIFIERS FOR THE GFS BUFR PRODUCTS

JUSA41 KWBC
JUSA42 KWBC
JUSB43 KWBC
JUSB44 KWBC
JUSB45 KWBC
JUSB46 KWBC
JUSX47 KWBC
JUSX48 KWBC
JUSX49 KWBC

THE EFFECTIVE DATE OF THIS CHANGE IS SOONER THAN SPECIFIED BY NWS 
POLICY. THE NORMAL ADVANCE LEAD TIME IS NOT PROVIDED SINCE NO 
ACTION BY USERS IS REQUIRED TO PREPARE FOR THE IMPLEMENTATION.  
NO SOFTWARE CHANGES BY USERS ARE NECESSARY FOR IMPLEMENTATION OF 
THIS CHANGE. THIS CHANGE WILL CORRECT TEMPERATURE ERRORS OF 2 TO 
3 DEGREES.  


IF YOU HAVE ANY QUESTIONS CONCERNING THESE CHANGES...PLEASE 
CONTACT: 

  JOHN H. WARD
  NCEP...GLOBAL MODELING BRANCH
  CAMP SPRINGS MARYLAND
  301-763-8000 X 7185
  JOHN.WARD@NOAA.GOV

NATIONAL TECHNICAL IMPLEMENTATION NOTICES ARE ONLINE AT  
/USE LOWERCASE/:

  HTTP://WWW.WEATHER.GOV/OS/NOTIF.HTM

$$
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