NOUS41 KWBC 221936
PNSWSH 

TECHNICAL IMPLEMENTATION NOTICE 08-99
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
236 PM EST MON DEC 22 2008

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

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

SUBJECT:  GLOBAL FORECAST SYSTEM CHANGES: EFFECTIVE 
          FEBRUARY 10 2009

EFFECTIVE TUESDAY FEBRUARY 10 2009...BEGINNING WITH THE 1200 
COORDINATED UNIVERSAL TIME /UTC/ RUN...THE GLOBAL ANALYSIS 
SYSTEM WILL BE MODIFIED TO INCLUDE CHANGES IN THE OBSERVATIONS 
USED IN THE ANALYSIS AND IN THE FORMULATION OF THE ANALYSIS. 
THESE CHANGES ARE EXPECTED TO IMPROVE PERFORMANCE OF THE 
GLOBAL FORECAST AND ASSIMILATION SYSTEM. 

THE CHANGES TO THE GLOBAL ANALYSIS SYSTEM /A GLOBAL 
APPLICATION OF THE GRID-POINT STATISTICAL INTERPOLATION /GSI/ 
SYSTEM/ INCLUDE:
      
  1. INCLUSION OF METOP IASI DATA
  2. USE OF VARIATIONAL QC
  3. CHANGE IN LAND/SNOW/ICE SKIN TEMPERATURE VARIANCE
  4. FLOW DEPENDENT REWEIGHTING OF BACKGROUND ERROR VARIANCES
  5. ADDITION OF BACKGROUND ERROR COVARIANCE INPUT FILE
  6. REDUCTION OF NUMBER OF AIRS WATER VAPOR CHANNELS USED
  7. USE OF NEW VERSION AND COEFFICIENTS FOR COMMUNITY 
     RADIATIVE TRANSFER MODEL
  8. MODIFICATION OF HEIGHT ASSIGNMENT FOR HEIGHT BASED WIND
     OBSERVATIONS
  9. MODIFICATION OF SURFACE LAND USE FILE TO REMOVE A FEW
     PERMANENT /~12/ GLACIAL POINTS TO IMPROVE SURFACE
     TEMPERATURE FORECASTS OVER THOSE POINTS. 

DATA DELIVERY TIMING WILL NOT BE IMPACTED BY THIS IMPLEMENTATION. 
THE GFS DELIVERY TIME WILL NOT CHANGE.

TEST DATA WILL BE AVAILABLE ON 22 DECEMBER VIA THE NCEP FTP 
SERVER AT THE FOLLOWING LOCATIONS /USE LOWERCASE LETTERS/: 

FTP://FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PARA/GFS.YYYYMMDD

FTP://FTPPRD.NCEP.NOAA.GOV/PUB/DATA/NCCF/COM/GFS/PARA/GDAS.YYYYMMDD

THERE WILL BE NO CHANGE IN THE FORMAT OR CONTENT OF THE DATA 
VIA ALL DISSEMINATION ROUTES THAT INCLUDE NOAAPORT...THE NWS 
PUBLIC FTP SERVER AND THE NCEP PUBLIC FTP SERVER. 

FOR QUESTIONS CONCERNING THESE CHANGES...PLEASE CONTACT: 

  JOHN H. WARD
  NCEP...GLOBAL MODELING BRANCH
  CAMP SPRINGS MARYLAND
  301-763-8000 X7185
  JOHN.WARD@NOAA.GOV
OR
  JOHN DERBER
  NCEP
  CAMP SPRINGS MARYLAND
  301-763-8000 X7740
  JOHN.DERBER@NOAA.GOV

NWS TECHNICAL IMPLEMENTATION NOTICES ARE AVAILABLE ONLINE AT 
/USE LOWERCASE/:

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

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