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EMC > GLOBAL BRANCH > GFS > IMPLEMENTATIONS
GLOBAL FORECAST SYSTEM

Upcoming Implementation:


Date

Title

Q3FY17 GSM v14.0.0 - implementation tentatively scheduled for July 19th, 2017 12 UTC

Effective on or about Tuesday June 27, 2017, beginning with the 1200 Coordinated Universal Time (UTC) run, the National Centers for Environmental Prediction (NCEP) will upgrade the GFS Analysis and Forecast System as follows:

  • Changes to the model components
  • Changes to the data assimilation and tropical storm relocation components
  • Changes to the post-processing
  • Changes to output products

1) Changes to the Global Forecast System Global Spectral Model (GSM) components

  • Implement GSM source code in NOAA Environmental Modeling System (NEMS) framework
  • Upgrade to asynchronous quilting for scalable and efficient write component in NEMS GSM, and replace spectral history file output (sigma files) with new nemsio binary files on model native grid. Documentation of nemsio format including data structure, interface, how to open, read, write, and MPI I/O support are at http://www.emc.ncep.noaa.gov/NEMS/nemsio.php and nemsio library at http://www.nco.ncep.noaa.gov/pmb/codes/nwprod/lib/nemsio
  • Implement Near Surface Sea Temperature (NSST) to replace Real-Time Global SST (RTGSST) to provide more realistic ocean boundary conditions
  • Upgrade deep & shallow convection schemes with scale- and aerosol-aware features along with convective cloudiness enhancement
  • Modify Rayleigh damping to improve temperature and wind forecasts in the upper stratosphere
  • Upgrade the land surface model to increase ground heat flux under deep snow; and unify snow cover fraction and snow albedo
  • Use new high-resolution MODIS-based snow-free albedo, maximum snow albedo, soil type and vegetation type
  • Upgrade surface layer parameterization scheme to modify the roughness-length formulation and introduce a stability parameter constraint in the Monin-Obukov similarity theory to prevent the land-atmosphere system from decoupling.

2) Changes to the Global Data Assimilation System (GDAS) and Tropical Storm Relocation:

  • Implement Near Sea-Surface Temperature (NSST) Analysis
  • Implement CrIS full resolution data assimilation capability
  • Implement readiness for new Geostationary Operational Environmental Satellite (GOES-16), Joint Polar Satellite System (JPSS-2) and COSMIC-2 (Constellation Observing System for Meteorology, Ionosphere and Climate) data assimilation capability
  • Extend Regional Advanced Television Infrared Observation Satellite (TIROS) Operational Vertical Sounder (ATOVS) Retransmission Services (RARS) and Direct Broadcast Network (DBNet) capability
  • Implement bug fix to cloud water increment in Gridpoint Statistical Interpolation (GSI)
  • Upgrade land surface type specification in Community Radiative Transfer Model (CRTM)
  • Update data monitoring for Megha-tropiques Sounder for Probing Vertical Profiles of Humidity (SAPHIR) and Global Precipitation Measurement (GPM) Microwave Imager (GMI) radiances.
  • Assimilate Visible Infrared Imaging Radiometer Suite (VIIRS) Atmospheric Motion Vectors (AMVs) and implement log-normal wind quality control for AMVs
  • Assimilate Geostationary Operational Environmental Satellite system (GOES) clear-air water vapor winds
  • Assimilate additional global navigation satellite system (GNSS) –Radio Occultation (RO) observations.
  • Modify pressure and hybrid coordinates transformation during the storm relocation.
  • Change relocation of the vorticity and divergence fields to the relocation of u,v wind components
  • Remove bogus Tropical Storm/Hurricane data for use in Data Assimilation.
  • Assimilate Global Hawk dropsonde data when available
  • Upgrade data assimilation monitoring package

3) Changes to the post-processing

  • Upgrade Post-Processing software to use new nemsio model output
  • Implement continuity equation to derive omega on grid space for new nems model output only
  • Modify interpolation procedure for all categorical fields including land mask, icing severity and precipitation types products to use nearest neighbor interpolation;
  • Generate hourly GFS Flux files directly by the post processor instead of GFS model
  • Visibility and second land mask are being added to pgrb2 files for all resolutions.
  • 2p5 degree resolution pgrb files will no longer be available on the public servers.
  • Remove category rain and correct Grib2 IDs for soil temperature and total column cloud fraction in GFS flux files.
  • Time label for SUNSD in GFS Flux files will be changed to instantaneous to be consistent with time label in GFS pressure Grib files.
  • The packing for GFS Flux files have been changed to complex packing to be consistent with packing method of GFS pressure Grib files.
  • Change interpolation method for CTP (In-Cloud Turbulence Potential) and CB cover (Horizontal Extent of Cumulonimbus) from 'linear' to 'nearest neighbor' to avoid averaging their own specific negative value with normal values when doing grid conversion

4) Changes to output products

With this upgrade the following changes will be noted on the NWS web services:
  • ftp://ftp.ncep.noaa.gov/pub/data/nccf/com/gfs/prod
  • http://www.ftp.ncep.noaa.gov/data/nccf/com/gfs/prod
  • http://nomads.ncep.noaa.gov
  • ftp://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/
  • http://weather.noaa.gov/pub/SL.us008001/ST.opnl/

  • Increase the frequency of station time-series BUFR data every hour to 120 hours, and then every 3 hours to 240 hours
  • Modify the list of stations from 1919 to 2021 on NOAAPORT and NCEP servers, for which BUFR data are generated for the GFS. The changes will also modify the lists of stations in the GFS BUFR sounding collectives disseminated on NOAAPORT. For the full list please reference this page: https://docs.google.com/document/d/15exFN-0W36cS4rNULALyh_qTJcl8hBBTBZozdRxM_0s/edit#
  • Correct a few errors in the original station list. Land/water designations were added for those stations that do not have the designations
  • Change station bufr sound file name from bufr3.STN_ID.YYYYMMDDHH to bufr.STN_ID.YYYYMMDDHH
  • Replace copygb2 by WGRIB2 in downstream products and change the basic angle of the initial production domain from 0 to -1 for all 0.25 degree; 0.5 degree; and 1.0 degree grib2 output; AWIPS 20km Puerto Rico grid;
  • Replace copygb2 by WGRIB2 in all AWIPS products and correct the resolution and component flag from 8 to 48 for AWIPS 160 grid; AWIPS 20km CONUS grid; AWIPS 20km AK grid; AWIPS 20km Puerto Rico grid and AWIPS Grid 213 (National - CONUS - Double Resolution Polar Stereographic 95km)
  • Add 925 mb for fields: HGT, TMP, VVEL, RH and U and V windows components to AWIPS Global Lat/Lon (1.0 deg) grid
  • Replace copygb2 by WGRIB2 in all GEMPAK grids and correct the resolution and component flag from 8 to 48 and basic angle of the initial production domain from 0 to -1

List of file name changes:

All files that had filename prefix "gdas1" will be renamed with filename prefix "gdas" (unless they are in the list of files to be discontinued).

Current Production File Name New Production File Name
gfs.tCCz.sgesprep
gfs.tCCz.sgmHprep
gfs.tCCz.sgpHprep
gfs.tCCz.sanl
gfs.tCCz.sfcanl
gfs.tCCz.sfHH
gfs.tCCz.bfHH
gdas1.tCCz.sanl
gdas1.tCCz.sfcanl
gdas1.tCCz.abias
gdas1.tCCz.abias_pc
gdas1.tCCz.abias_air
gdas1.tCCz.radstat
gdas1.tCCz.sfHH
gdas1.tCCz.bfHH
gdas1.tCCz.pgrb2.1p00.anl
gdas1.tCCz.pgrb2.1p00.anl.idx
gdas1.tCCz.pgrb2.0p25.anl
gdas1.tCCz.pgrb2.0p25.anl.idx
gdas1.tCCz.pgrb2.1p00.fHHH
gdas1.tCCz.pgrb2.1p00.fHHH.idx
gdas1.tCCz.pgrb2.0p25.fHHH
gdas1.tCCz.pgrb2.0p25.fHHH.idx
gdas1.tCCz.sfluxgrbfHH.grib2
sfcanl_YYYYMMDDCC_ensmean
sfcanl_YYYYMMDDCC_memXXX
sfg_YYYYMMDDCC_fhrHH_memXXX
bfg_YYYYMMDDCC_fhrHH_memXXX
sfg_YYYYMMDDCC_fhrHH_ensmean
bfg_YYYYMMDDCC_fhrHH_ensmean
sfg_YYYYMMDDCC_fhrHHs_memXXX
gfs.tCCz.atmges.nemsio
gfs.tCCz.atmgmH.nemsio
gfs.tCCz.atmgpH.nemsio
gfs.tCCz.atmanl.nemsio
gfs.tCCz.sfcanl.nemsio
gfs.tCCz.atmfHHH.nemsio
gfs.tCCz.sfcfHHH.nemsio
gdas.tCCz.atmanl.nemsio
gdas.tCCz.sfcanl.nemsio
gdas.tCCz.abias
gdas.tCCz.abias_pc
gdas.tCCz.abias_air
gdas.tCCz.radstat
gdas.tCCz.atmfHHH.nemsio
gdas.tCCz.sfcfHHH.nemsio
gdas.tCCz.pgrb2.1p00.anl
gdas.tCCz.pgrb2.1p00.anl.idx
gdas.tCCz.pgrb2.0p25.anl
gdas.tCCz.pgrb2.0p25.anl.idx
gdas.tCCz.pgrb2.1p00.fHHH
gdas.tCCz.pgrb2.1p00.fHHH.idx
gdas.tCCz.pgrb2.0p25.fHHH
gdas.tCCz.pgrb2.0p25.fHHH.idx
gdas.tCCz.sfluxgrbfHH.grib2
gdas.tCCz.sfcanl.ensmean.nemsio
gdas.tCCz.sfcanl.memXXX.nemsio
gdas.tCCz.atmfHHH.memXXX.nemsio
gdas.tCCz.sfcfHHH.memXXX.nemsio
gdas.tCCz.atmfHHH.ensmean.nemsio
gdas.tCCz.sfcfHHH.ensmean.nemsio
gdas.tCCz.atmfHHHs.memXXX.nemsio

List of files removed:

The following surface analysis, bufr dump and prepbufr files will no longer be generated:
  • gdas1.tCCz.*.tm00.bufr_d.unblok
  • gdas1.tCCz.*.tm00.bufr_d.unblok.nr
  • gfs.tCCz.prepbufr.unblok
  • gfs.tCCz.prepbufr.unblok.nr
  • gfs.tCCz.pgrb2.2p50.fHHH (where HHH is 000 to 384)
  • gdas1.tCCz.prepbufr.unblok
  • gdas1.tCCz.prepbufr.unblok.nr
  • sfcanl_CDATE_ensmean
  • sfcanl_CDATE_mem001~080

Files with the same content will continue to be available without the "unblok" filename qualifier (and with the change in prefix for gdas files). Eg, file gdas1.t00z.adpupa.tm00.bufr_d.unblok will be available as gdas.t00z.adpupa.tm00.bufr_d and file gfs.t00z.prepbufr.unblok.nr will be available as gfs.t00z.prepbufr.nr. There is one exception to the pattern in that gdas1.tCCz.sfcshp.tm00.bufr_d.unblok will be available as gdas.tCCz.sfcshp.tm00.bufr_d.nr.

NCEP urges all users to ensure their decoders can handle changes in content order, changes in the scaling factor component within the product definition section (PDS) of the GRIB files, and volume changes. These elements may change with future NCEP model implementations. NCEP will make every attempt to alert users to these changes before implementation.

For questions regarding these changes, please contact:

Vijay Tallapragada
NCEP/Global Climate and Weather Modeling Branch
College Park, MD
301­683­3672
Vijay.Tallapragada@noaa.gov

For questions regarding the data flow aspects, please contact:

Carissa Klemmer
NCEP/NCO Dataflow Team Lead
College Park, MD
301­683­0567
ncep.list.pmb­-dataflow@noaa.gov

NWS National Technical Implementation Notices are online at:

http://www.weather.gov/om/notif.htm


_________________________________________________________________________________________________________________

Recent Implementations:


Date

Title

Q3FY16 GSM v13.0.2 - implementation completed May 11th, 2016 12 UTC

Effective on or about Tuesday May 11, 2016, beginning with the 1200 Coordinated Universal Time (UTC) run, the National Centers for Environmental Prediction (NCEP) will upgrade the GFS Analysis and Forecast System as follows:   - Changes to the data assimilation components
  - Changes to the model components
  - Addition of hourly gridded output through 120 hours
  - Addition of five layers in the upper stratosphere in gridded output
  - Addition of new product fields
  - Product removals


Read full TIN: http://www.nws.noaa.gov/os/notification/tin16-11gfs_gdasaaa.htm

1) Changes to the Global Data Assimilation System (GDAS):

- Upgrade the 3D Hybrid Ensemble-Variational to 4D Hybrid Ensemble-Variational Data Assimilation System 4D increments are constructed by figuring out best combination of 4D ensemble perturbations. The weights for ensemble members are kept constant throughout the assimilation window. The 4D-Hybrid uses 50 outer and 150 inner iterations with variational quality control turned on after 25 iterations. Tangent Linear Normal Mode Constraint (TLNMC) and Digital Filter Initialization (DFI) are used in the ensembles while additive error inflation is removed. Ozone cross covariances are in the 4D-Hybrid.  Localization is recued to 50 percent in the troposphere and the weights for static and ensemble are kept at 12.5 percent and 87.5 percent respectively.
- Assimilate all sky Advanced Microwave Sounding Unit (AMSU-A) Radiances
- Assimilate Advanced Very High Resolution Radiometer (AVHRR) winds
and monitor Visible Infrared Imaging Radiometer Suite (VIIRS) winds
- Implement Geostationary Operational Environmental Satellites – R series (GOES-R) data readability
- Update Community Radiative Transfer Model (CRTM) to v2.2.1 with
bug fixes in wind direction, use of FAST Microwave Emissivity Models (FASTEM-6 and FASTEM-X) reflection correction for cloudy situations
- Improve bias correction for aircraft observations
- Modify relocation and storm tracking to allow hourly tropical cyclone
relocation
- Modify thinning/weight in time for Atmospheric Motion Vectors (AMVs) and radiances
- Upgrade data assimilation monitoring package


2) Model changes to the GFS Global Spectral Model and post-processing software:

- Correct the land surface characteristics for grassland and cropland categories to reduce summertime warm and dry biases over Great Plains
- Upgrade convective gravity wave drag
- Upgrade tracer adjustment in the semi-Lagrangian dynamic core
- Upgrade the NCEP Unified Post Processing (UPP) software to v7.0
- Implement Global Current Icing Potential analysis (G-CIP) products


3) Output product changes

All operational products below can be found on any of following NCEP or NWS servers:

ftp://ftp.ncep.noaa.gov/pub/data/nccf/com/gfs/prod
http://www.ftp.ncep.noaa.gov/data/nccf/com/gfs/prod
http://nomads.ncep.noaa.gov
ftp://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/
http://weather.noaa.gov/pub/SL.us008001/ST.opnl/

- Add new Global Forecast Icing Severity (G-FIS) icing severity parameter (ICSEV Icing Severity)

  gfs.tCCs.pgrb2.0p25.fFFF
  gfs.tCCs.pgrb2.0p50.fFFF
  gfs.tCCs.pgrb2.1p00.fFFF

    Where CC is 00, 06, 12, 18
    Where FFF is 000 to 384

- Improve Global Forecast Icing Potential (ICIP) products

  WAFS_blended_YYYYMMDDCCfFF.grib2

    Where FF is 06 to 36

- Include hourly forecasts out to 120 hr

  gfs.tCCz.pgrb2.0p25.fFFF
  gfs.tCCz.pgrb2b.0p25.fFFF

    Where FFF is 000, 001, 002, 003, 004...120

- Add grib filter and GDS/OpenDAP availabilty of the 2.5 deg hourly forecasts in NOMADS.

- filter_gfs_0p25_1hr.pl (grib filter link)
- gfs_0p25_1hr (
OpenDAP-alt link)

At this time data will not be available for testing until it goes into operations.

- Add five more vertical levels (7, 5, 3, 2, and 1 hPa) for the variables geopotential height (HGT), temperature (TMP), relative humidity (RH), U- and V- components of wind (UGRD and VGRD) and ozone mixing ratio (O3MR)

  gfs.tCCz.pgrb2.0p25.fFFF, gfs.tCCz.pgrb2b.0p25.fFFF
  gfs.tCCz.pgrb2.0p50.fFFF, gfs.tCCz.pgrb2b.0p50.fFFF
  gfs.tCCz.pgrb2.1p00.fFFF, gfs.tCCz.pgrb2b.1p00.fFFF
  gfs.tCCz.pgrb2.2p50.fFFF   

    Where FFF is forecast hours from 000 to 384

- Replace 775 hPa state variables with 750 hPa in the GFS WAFS grids 37-44 for UGRD, VGRD, TMP, RH, HGT

  On NCEP Servers:

  wafsgfs_L_tCCz_intdskFFF.grib2
  wafsgfs_P_tCCz_intdskFFF.grib2

  On NWS Servers:

  fh.0FFF_tl.press_ar.octant(ijklmno)   

    Where FFF is 000-120

- Add GDAS ABIAS air BUFR file

  gdas1.tCCz.abias_air

- Modify the list of stations on NOAAPORT and NCEP servers, for which BUFR data are generated for the GFS.  The changes will also modify the lists of stations in the GFS BUFR sounding collectives disseminated on NOAAPORT. For the full list please reference this page:

http://www.nco.ncep.noaa.gov/pmb/changes/gfs_upgrade_2016.shtml


The following changes to NOAAPORT are detailed below with the following WMO headers for each grid:

http://www.nco.ncep.noaa.gov/pmb/changes/gfs_20kmAWIPS_grids.shtml

- Alaska region grid 217 (20km) has been modified to expand latitude from 30N to 35N and longitude from 173W to 170W.

- The Maximum and Minimum Temperatures (TMAX, TMIN) Product Definition Template 4.8 will correct a mistake in the second fixed surface from “255 0 2” to “255 0 0” for the following grids:

  Alaska region 20km
  Pacific region 20km
  Puerto Rico 0.25deg
  CONUS 20km

- The Water Equivalent of Accumulated Snow Depth (WEASD) WMO headers were incorrectly labeled for forecast hours 186, 198, 210, 222 and 234. The following changes will be applied to each grid below:

  CONUS 20km: LSRU98 -> ZSNZ98
  Alaska 20km: LSRU98 -> ZSBZ98
  Pacific Region 20km: LSRU98 -> ZSEZ98

  Puerto Rico 0.25deg: LSRU98 -> ZSFZ98

- The Alaska region grid 217 (20km) had some incorrectly labeled forecast hours in the grid identifier WMO header. This will be addressed so all Alaska WMO products have A1 = B

- Addition of GRIB2 20 km gridded product over Pacific Region (Mercator) to NOAAPORT

  Runs 4 times per day at 00z, 06z, 12z and 18z

  WMO headers will be as follows:

  T1 = Y for forecast hours: 00, 06, 12, 15, 18, 24, 30, 36, 42, 48, 60, 72, 84, 96, 108,120, 132, 144, 156, 168, 180, 192, 204, 216, 228, 240

  T1 = Z for forecast hours: 03, 09, 15, 21, 27, 33, 39, 45, 51, 54, 57, 63, 66, 69, 75, 78, 81, 90, 102, 114, 126, 138, 150, 162, 174, 186, 198, 210, 222, 234

  T2 specifies the parameters as follows:

     T = Temperature, TMIN, TMAX; H = Height;
     5-wave geopotential height; O = Vertical velocity;
     R = Relative humidity; C = Absolute vorticity;
     U = u-component of wind; V = v-component of wind;
     P = Pressure; Pressure reduce to Mean Sea level;
     B = Vertical speed shear; E = Total precipitation;
     G = Convective precipitation; Q = Best Lifted Index;
     W = Convective Available Potential Energy;
     Y = Convective Inhibition; X = Surface Lifted Index;
     F = Precipitable Water; M = Precipitable Water;
     S = Water Equivalent of Accumulated Snow Depth;

  A1 = E* Grid 20 km, Pacific Region

  *Was incorrectly labeled "F" in the previous advertised TIN 14-54

  A2 specifies the forecast hours as follows:

     A=00; B=06; C=12; D=18; E=24; F=30; G=36; H=42;
     I=48; J=60; K=72; L=84; M=96; N=108; O=120;
     P=132; Q=144; R=156; S=168; T=180; U=192; V=204;
     W=216; X=228; Y=240 (Note: T1 is Y)

     B=03; E=09; H=15; K=21; L=27; O=33; P=39; Q=45;
     R=51; M=54; S=57; Z=63; N=66; Z=69; Z=75; T=78;
     Z=81; U=90; V=102; W=114;
     Z=126; 138; 150; 162; 174; 186; 198; 210; 222;
     234 (Note: T1 is Z)

    ii specifies level as follows:

     99=1000mb; 93=975mb; 95=950mb; 92=925mb; 90=900mb;
     91=875 mb; 85=850mb; 82=825mb; 80=800mb; 77=775mb;
     75=750mb; 72=725mb; 70=700mb; 67=675 mb; 65=650mb;
     62=625 mb; 60=600mb; 57=575mb; 55=550mb; 52=525mb;

     50=500mb; 45=450mb;40=400mb; 35=350mb; 30=300mb;
     25=250mb; 20=200mb; 15=150mb; 10=100mb;
     73=High, Mid, Low cloud bottom level; 86=Boundary Layer;
     89=Reduced to Sea Level; 94=Level of the 0 deg. C isotherm;
     96=Maximum wind level;
     97=Level of the Tropopause, potential vorticity surface;
     98=Surface of Earth; 00=Entire Atmosphere

  See the following link for a full list of WMO headers:

    http://www.nco.ncep.noaa.gov/pmb/changes/gfs_pac_wmo.txt


4) Output product removals

NCEP has been working to remove low resolution legacy products in lieu of higher resolution grids. Last year NCEP added new higher resolution grids to NOAAPORT in preparation for removing the legacy grids. Due to the positive responses received from the NCEP Public Information Statement 16-04, Removal of Legacy Global Forecast System (GFS) Gridded Output, the following products will be removed with this upgrade:

- Remove the GFS grid 212, 40km Regional CONUS from NOAAPORT

  WMO Headers:

http://www.nco.ncep.noaa.gov/pmb/changes/gfs_AWIPS_grids.shtml


To find the replacement products please reference this TIN:

http://www.nws.noaa.gov/os/notification/tin14-54gfs_noaaport.htm

- Removal Vessel Sea Ice and Fog on grid 232, 1 deg Northern

Hemisphere from NOAAPORT

  WMO Headers:

http://www.nco.ncep.noaa.gov/pmb/changes/omb_AWIPS_grids.shtml

- Removal of 1.25 deg GRIB1 GFS WAFS products from the NWS

http/ftp server:

weather.noaa.gov/pub/SL.us008001/ST.opnl/MT.gfs_CY.CYCLE/RD.YYYY

MMDD/PT.grid_DF.gr1/fh.FFF_tl.press_ar.octant[ijklmnop]

ftp://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/MT.gfs_CY.CYCLE/RD.

YYYYMMDD/PT.grid_DF.gr1/fh.FFF_tl.press_ar.octant[ijklmnop]

  where CYCLE is 00, 06, 12, 18
  where YYYYMMDD is Year, Month, Day
  where FFF is forecast hour from 000-120
 

To find the replacement product please reference this TIN:

http://www.nws.noaa.gov/os/notification/pns16-04gfs_removal.htm

- Removal of 1.25 deg GRIB1 GFS WAFS products from the NCEP

http/ftp server:

http://nomads.ncep.noaa.gov/pub/data/nccf/pcom/gfs/xtrn.wfsgfs*
ftp://ftp.ncep.noaa.gov/pub/data/nccf/pcom/gfs/xtrn.wfsgfs*

To find the replacement product please reference this TIN:

http://www.nws.noaa.gov/os/notification/pns16-04gfs_removal.htm


5) Parallel data available

Starting in April 1, 2016 all parallel data sets will be available on the following servers:

http://para.nomads.ncep.noaa.gov/pub/data/nccf/com/gfs/para


For more information on this GFS upgrade, please see EMC real-time and retrospective parallels and verification pages:

http://www.emc.ncep.noaa.gov/gmb/noor/4dGFS/synergy%20announcementjan08.htm


NCEP urges all users to ensure their decoders can handle changes in content order, changes in the scaling factor component within the product definition section (PDS) of the GRIB files, and volume changes. These elements may change with future NCEP model implementations. NCEP will make every attempt to alert users to these changes before implementation.

For questions regarding these changes, please contact:

     Vijay Tallapragada
     NCEP/Global Climate and Weather Modeling Branch
     College Park, MD

     301-683-3672

     Vijay.Tallapragada@noaa.gov

For questions regarding the data flow aspects of these data

sets, please contact:

     Carissa Klemmer
     NCEP/NCO Dataflow Team Lead
     College Park, MD

     301-683-0567

     ncep.list.pmb-dataflow@noaa.gov

NWS National Technical Implementation Notices are online at:

   http://www.nws.noaa.gov/os/notif.htm


_________________________________________________________________________________________________________________

Previous Implementations:


Date

Title

2015011512 GSM v12.0.0 - implementation completed January 14th, 2015

2012090512 Correction to Land Surface Model in Global Forecast System and associated cool and moist bias in near surface temperature and moisture fields (Click to read more)
2012052212 Hybrid EnKF - 3DVar GSI data assimilation (Click to read more)
2011050914 GFS 9.0.1 (Click to read more)
2010072712 T574 W/ NEW PHYSICS - July 27th 2010 (Click to read more)

_________________________________________________________________________________________________________________

Historical upgrades


Click here to view full list of past upgrades