NOUS41
KWBC 221605
Public
Information Statement, Comment Request
National
Weather Service Headquarters Washington, DC
1105
AM EST Tue Jan 22 2013
To: Subscribers:
-Family of Services
-NOAA Weather Wire Service
-Emergency Managers Weather
Information Network
-NOAAPORT
Other NWS Partners, Users and
Employees
From: John Derber,
Acting Chief
Global Climate and Weather Modeling
Branch
NCEP/Environmental Modeling Center
Subject: Soliciting Public Comments through February
20,
2013, on the Removal of NCEP’s Legacy
Global
Forecast System (GFS) Low-Resolution
Products.
The
National Centers for Environmental Prediction (NCEP) is
proposing to stop producing some legacy low-resolution
gridded
products from the Global Forecast System (GFS), and stop
disseminating them via NOAAPORT and the NWS ftp
server. The NWS
is seeking comments on this proposed change through
February 20,
2013.
The
operational GFS model is currently run at a resolution of
T574L64, approximately 27 km. Today output is made available
from the GFS on grids ranging in resolution from 5km up
to
5 degrees latitude/longitude. Many of these legacy low-resolution
grids are available for limited forecast hours and
fields, and
are not produced for all cycles of the GFS. The same
information
is provided on finer-resolution grids. In addition,
many of these
products have been removed from the NCEP ftp server and are
only
distributed via NOAAPORT and the NWS ftp server.
Removing these
legacy products will free up compute and network resources
for
newer products.
Operational
GFS output is distributed via NOAAPORT, the NWS FTP
server, the NOMADS system
and the NCEP ftp server. Output is available from 00-192 hours
every 3 hours and from 204-384 hours every 12 hours for
the 00Z,
06Z, 12Z, 18Z cycle times. Output is available on
multiple
resolutions and output grids, including 0.5 degree, 1.0
degree,
and 2.5 degree grids. A catalogue of GFS output
products and
their availability on multiple ftp servers can be found
at
http://www.nco.ncep.noaa.gov/pmb/products/
Listed
below are the gridded products available on NOAAPORT and
the NWS ftp server that NCEP is proposing to
remove.
Grid Resolution
Area Map
Projection
------------------------------------------------------
Family
of Service (FOS) grids
#21 5x2.5
0-180E, 0-90N
latitude/longitude
#22 5x2.5
180W-0, 0-90N
latitude/longitude
#23 5x2.5
0-180E, 90S-0
latitude/longitude
#24 5x2.5
180W-0, 90S-0
latitude/longitude
#25 5x5 0-355E, 0-90N latitude/longitude
#26 5x5 0-355E, 90S-0 latitude/longitude
AWIPS
grids
#201 381 km
N. Hemisphere Polar
Stereographic
#202 190.5 km
CONUS Polar
Stereographic
#203 190.5 km
Alaska Polar
Stereographic
#204 160 km
Hawaii Mercator
#205 190.5 km
Puerto Rico Polar
Stereographic
WAFS
grids -- only the 00Z cycle grids for hours 96 through 168
are proposed for removal
#37 1.25x1.25
0-90N, 330-60E
latitude/longitude
#39 1.25x1.25
0-90N, 150-240E latitude/longitude
#40 1.25x1.25
0-90N, 240-330E latitude/longitude
The
AWIPS grid #201 products are available on NOAAPORT in both
GRIB1
and GRIB2 format, and both are proposed for
removal. More
information about the model grids listed above is
available at
http://www.nco.ncep.noaa.gov/pmb/docs/on388/tableb.html
WMO
headers for these products slated for removal are listed at:
http://www.nco.ncep.noaa.gov/pmb/changes/docs/gfs_legacy_remove.shtml
In
addition to being available on NOAAPORT, many of these grids
are available on the NWS FTP server at:
ftp://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/MT.mrf_CY.00/RD.yyyymmdd/PT.grid_DF.bb/
and
ftp://tgftp.nws.noaa.gov/SL.us008001/ST.opnl/MT.gfs_CY.zz/RD.yyyymmdd/PT.grid_DF.bb/
where yyyymmdd is the 4-digit
year, 2-digit month, and 2-digit
day, and zz is the 2-digit
model cycle.
NWS
will evaluate all comments to determine whether to proceed
with this change. If approved, a TIN will be issued
giving
30
days notice of the implementation date.
Send
comments on this proposal to:
John Derber
NWS/NCEP Environmental Modeling Center
College Park, MD
or
Rebecca Cosgrove
NWS/NCEP Central Operations
College Park, MD
National
Public Information Statements are online at:
http://www.weather.gov/os/notif.htm
$$