-------- Original Message --------
832
NOUS41 KWBC 181940
PNSWSH
Technical Implementation Notice 11-14
National Weather Service Headquarters Washington DC
340 PM EDT Mon Apr 18 2011
To: Subscribers:
-Family of Services
-NOAA Weather Wire Service
-Emergency Managers Weather Information Network
-NOAAPORT
Other NWS Partners, Users and Employees
From: Tim McClung
Science Plans Branch Chief
Office of Science and Technology
Subject: Climate Forecast System (CFS) Change
Effective July 5, 2011, beginning with the 1200 Coordinated
Universal Time (UTC) run, the National Centers for Environmental
Prediction (NCEP) will change the output grid of all of the nine
(9) parameters in two (2) files from the Data Assimilation cycle
of the Climate Forecast System (CDAS1) from 0.5x0.5 degree
latitude-longitude to a 27 km Gaussian Grid (1760x880).
The nine (9) parameters that will be affected in each of the two
(2) files are:
CWATclm - atmospheric column cloud water [kg/m2]
HGThlev1 - hybrid level 1 geopotential height [gpm]
PRESsfc - surface pressure [Pa]
PWATclm - atmospheric column precipitable water [kg/m2]
SPFHhlev1 - hybrid level 1 specific humidity [kg/kg]
TMPhlev1 - hybrid level 1 temperature [K]
UGRDhlev1 - hybrid level 1 u wind [m/s]
VGRDhlev1 - hybrid level 1 v wind [m/s]
The CDAS1 output files are available on the NCEP server at:
http://www.ftp.ncep.noaa.gov/data/nccf/com/cfs/prod/
and on NOMADS at:
http://nomads.ncep.noaa.gov/pub/data/nccf/com/cfs/prod/
The grid change will occur in the following two (2) files only:
cdas1.txxz.splgrbanl.grib2
cdas1.txxz.splgrbf06.grib2
where xx is 00, 06, 12, 18.
A set of test files is available at:
http://cfs.ncep.noaa.gov/pub/raid0/cfsv2/sample.spl.new
There will be no changes in the delivery time of CFS products.
NCEP encourages all users to ensure their decoders are flexible
and are able to adequately handle changes in content order,
changes in the scaling factor component within the product
definition section (PDS) of the GRIB files, and also any volume
changes which may be forthcoming. These elements may change with
future NCEP model implementations. NCEP will make every attempt
to alert users to these changes prior to any implementations.
For questions regarding these changes, please contact:
Suranjana Saha
NCEP/EMC, Global Climate and Weather Modeling Branch
Camp Springs, Maryland
301-763-8000 x 7052
Suranjana.Saha@xxxxxxxx
John H. Ward
NCEP/EMC, Global Climate and Weather Modeling Branch
Camp Springs, Maryland
301-763-8000 x 7185
John.Ward@xxxxxxxx
For questions regarding the dataflow aspects of these datasets,
please contact:
Rebecca Cosgrove
NCEP/NCO Dataflow Team
Camp Springs, Maryland 20746
301-763-8000 x 7198
ncep.list.pmb-dataflow@xxxxxxxx
NWS National Technical Implementation Notices are online at:
http://www.weather.gov/os/notif.htm
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