"Jon O'Rourke"
Notice that Meteociel states that the parallel suite replaced the
operational GFS output 2 days ago.

.... It looks as if 15th December was *always* the date intended for
change-over, so the Meteociel notice was in error:-

http://www.weather.gov/os/notificati...fs_changes.txt

From that, extracts ....

EFFECTIVE DECEMBER 15 2009...BEGINNING WITH THE 1200
COORDINATED UNIVERSAL TIME /UTC/ RUN...THE NATIONAL CENTERS
FOR ENVIRONMENTAL PREDICTION /NCEP/ WILL UPGRADE SEVERAL
COMPONENTS OF THE GLOBAL FORECAST SYSTEM /GFS/.

NEW DATA SOURCES AND IMPROVED NUMERICAL TECHNIQUES WILL BE
INCLUDED IN THE GRIDPOINT STATISTICAL INTERPOLATION /GSI/
ANALYSIS.

THE POST PROCESSORS USED FOR THE GLOBAL FORECAST SYSTEM
/GFS/ AND THE GLOBAL DATA ASSIMILATION SYSTEM /GDAS/ WILL BE
UNIFIED AND TWO MINOR CHANGES WILL BE INTRODUCED INTO THE GLOBAL
FORECAST MODEL. UNIFICATION OF THE POST PROCESSING CODES WILL
RESULT IN SLIGHTLY LESS SMOOTH FIELDS IN THE GDAS.

IN ADDITION THE ACCURACY IN THE FORMULATION OF A NUMBER OF
DIAGNOSTIC VARIABLES WILL BE IMPROVED AND ADDITIONAL
PARAMETERS WILL BE ADDED TO THE MODEL OUTPUT FILES.

THE ANALYSIS CHANGES INCLUDE:

-ASSIMILATING TROPICAL STORM PSEUDO SEA-LEVEL PRESSURE
OBSERVATIONS
-ASSIMILATING NOAA-19 HIRS/4 AND AMSU-A BRIGHTNESS
TEMPERATURE OBSERVATIONS
-ASSIMILATING RARS 1B DATA
-ASSIMILATING NOAA-18 SBUV/2 AND AURA OMI OZONE OBSERVATIONS.
MONITOR NOAA-19 AND METOP-2 GOME OZONE OBSERVATIONS
-ASSIMILATING EUMETSAT-9 ATMOSPHERIC MOTION VECTORS
-USING UNIFORM THINNING MESH FOR BRIGHTNESS TEMPERATURE DATA
-IMPROVING ASSIMILATION OF GPS RADIAL OCCULTATION /RO/ DATA
/QC... RE-TUNED OBSERVATION ERRORS/
-ADDING DRY MASS PRESSURE CONSTRAINT
-USING GODDARD MODELING AND ASSIMILATION OFFICE/EMC MERGED
CODE INCLUDING HOOKS FOR 4DVAR AND OBSERVATION SENSITIVITY
-UPDATING BACKGROUND ERROR COVARIANCE FILE

THE PARAMETERS WITH IMPROVED FORMULATIONS IN THE POST PROCESSOR
INCLUDE:

-VORTICITY
-ISENTROPIC POTENTIAL VORTICITY /IPV/
-DYNAMIC TROPOPAUSE FIELDS
-PLANETARY BOUNDARY LAYER /PBL/ MEAN RH
-BEST CAPE/CIN
-BEST LIFTED INDEX
-LFM 0.33-1.00 RH

THE NEW PARAMETERS FOR THE GDAS INCLUDE:

-UNFILTERED SEA LEVEL PRESSURE



--
Martin Rowley
West Moors, East Dorset (UK): 17m (56ft) amsl
Lat: 50.82N Long: 01.88W
NGR: SU 082 023