UPGRADE OF THE NCEP GLOBAL FORECAST SYSTEM-ADMIN NOTICE NOUS41 KWBC

• To: nws-changes@xxxxxxxxxxxxxxxx
• Subject: UPGRADE OF THE NCEP GLOBAL FORECAST SYSTEM-ADMIN NOTICE NOUS41 KWBC
• From: Jeff Weber <jweber@xxxxxxxxxxxxxxxx>
• Date: Wed, 27 Apr 2005 12:46:42 -0600 (MDT)

088
NOUS41 KWBC 271802
PNSWSH

TECHNICAL IMPLEMENTATION NOTICE 05-33
NATIONAL WEATHER SERVICE HEADQUARTERS WASHINGTON DC
200 PM EDT WED APR 27 2005

TO:       FAMILY OF SERVICES /FOS/ SUBSCRIBERS...NOAA WEATHER
          WIRE SERVICE /NWWS/ SUBSCRIBERS...EMERGENCY MANAGERS
          WEATHER INFORMATION NETWORK /EMWIN/ SUBSCRIBERS...OTHER
          NATIONAL WEATHER SERVICE /NWS/ CUSTOMERS AND
          PARTNERS...NWS EMPLOYEES

FROM:     PAUL HIRSCHBERG
          CHIEF...SCIENCE PLANS BRANCH
          OFFICE OF SCIENCE AND TECHNOLOGY /OST/

SUBJECT:  UPGRADE OF THE NCEP GLOBAL FORECAST SYSTEM  EFFECTIVE:
          MAY 31 2005

EFFECTIVE MAY 31 2005...BEGINNING WITH THE 1200 COORDINATED
UNIVERSAL TIME /UTC/ RUN...THE NATIONAL CENTERS FOR ENVIRONMENTAL
PREDICTION /NCEP/ WILL UPGRADE THE GLOBAL FORECAST SYSTEM /GFS/
TO IMPROVE ITS ACCURACY AND PRODUCTS.

THIS UPGRADE INVOLVES INCREMENTAL IMPROVEMENTS TO THE ANALYSIS
AND FORECAST OF THE GFS. DETAILS OF THESE CHANGES INCLUDE:

ANALYSIS CHANGES:

 - INCREASE HORIZONTAL RESOLUTION TO T382.
 - ASSIMILATE AQUA AIRS AND AMSU-A BRIGHTNESS TEMPERATURES.
 - MODIFY THINNING ALGORITHM FOR BRIGHTNESS TEMPERATURES.
 - ADD SURFACE MICROWAVE EMISSIVITY MODEL OVER SNOW AND ICE.
 - MODIFY BRIGHTNESS TEMPERATURE QUALITY CONTROL ALGORITHM
   TO CHECK FOR THE PRESENCE OF CLOUDS IN IR FIELDS OF VIEW.

FORECAST MODEL CHANGES:

 - HORIZONTAL RESOLUTION INCREASED FROM T254 (~55 KM) 64 LAYERS TO
   T382 (~35KM) 64 LAYERS FOR FORECAST HOURS 0-180.
 - HORIZONTAL RESOLUTION INCREASED FROM T126 (~100 KM) 42 LAYERS
   TO T190 (~70 KM) 64 LAYERS FOR FORECAST HOURS GREATER
   THAN 180.
 - ADDITION OF THE NOAH LAND SURFACE MODEL WITH 4 SOIL LAYERS.
 - NEW SEA ICE MODEL.
 - REDUCED VERTICAL DIFFUSION.
 - ENHANCED MOUNTAIN BLOCKING.

THIS UPGRADE WILL NOT CHANGE GFS PRODUCTS SENT OVER NOAAPORT.
NCEP CENTRAL OPERATIONS IS CURRENTLY RUNNING A REAL-TIME PARALLEL
RUN OF THE T382 GFS. RESULTS FROM THESE PARALLEL RUNS CAN BE
VIEWED AT /USE LOWER CASE LETTERS/:

  HTTP://WWW.NCO.NCEP.NOAA.GOV/PMB/NWPARA/ANALYSIS/

FOR QUESTIONS CONCERNING THESE CHANGES...PLEASE CONTACT:

 DR. MARK IREDELL
 NCEP...GLOBAL MODELING BRANCH
 CAMP SPRINGS MARYLAND
 PHONE: 301 763 8000 X7231
 EMAIL: MARK.IREDELL@xxxxxxxx

OR

 KEN CAMPANA
 NCEP...GLOBAL MODELING BRANCH
 CAMP SPRINGS MARYLAND
 PHONE: 301 763 8000 X7228
 EMAIL: KENNETH.CAMPANA@xxxxxxxx

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

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

$$
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