20050401: NCEP update (fwd)

• To: nws-changes@xxxxxxxxxxxxxxxx
• Subject: 20050401: NCEP update (fwd)
• From: John Ward <wd22jw@xxxxxxxxxxxxxxxxxxxx>
• Date: Friday, April 01, 2005 9:47 AM -0500

---------- Forwarded Message ----------

1.      Recent problems with the delivery of NCEP forecast model data to the 
NWS TOC FTP
server have been resolved.  The majority of model data is now arriving within 1
minute of it's creation on the Central Computer System.

2.      The Frost system is expected to be back in service by 4 April.  On 18 
April the
Snow system will be taken out of service for about 6 weeks.  The GPFS file 
system on
Snow will be mirrored to Frost prior to Snow being taken out of service.  A 
subset
of forecast model output and all observational data is currently being made
available on the Snow system. During the Snow upgrade the model data will be
available on Snow.  Once the upgrades are complete on both the Frost and Snow
systems, this subset of production data will be made available to the users of 
both
the Frost and Snow systems.

3.      The resolution increase of the GFS from T254 to T382 has been
tentatively scheduled for Tuesday, 31 May.  The highest resolution
portion of the forecast is being extended from 84 to 180 hours.  From 180 to 384
hours the model resolution will increase to T190.  The vertical resolution will
remain at 64 levels to 180 hours and will increase from 42 to 64 levels beyond 
180
hours.  A couple of minor changes will be made to the pressure level GRIB files.
These changes include:

    A.  Soil moisture and soil temperature -- Currently we provide soil moisture
and temperature parameters that cover the depth of 10 - 200 cm below ground.  
We are
removing these parameters and replacing each of them with three new parameters 
in
more discreet layers (10-40 cm, 40-100 cm, & 100-200 cm).

    B.  Potential Vorticity Unit (PVU) surfaces.  We currently make available
heights, temps, pressures, and winds on the +2 and -2 PVU surfaces.  We are
incorrectly labeling these levels in the GRIB PDS section from what is defined 
by
the WMO.  They are currently mislabeled as ±0.002 PVU surface.  We will correct 
this
when the T382 is implemented.

    As a result of these changes, the size of these files is
expected to increase by only 0.2 MB.

4.   The last planned upgrade of the Eta model in the North American Meso-scale
(NAM) system has been scheduled for 03 May 2005.  At that time the Eta codes 
will be
frozen until they are replaced with the Weather Research & Forecast (WRF) model 
in
the spring of 2006.

5.   In May the resolution of the Rapid Update Cycle (RUC) will be
increased from 20 to 13 km.  There will be no change in format or
content of forecast model output.  At some point in the future, 13 km output 
will
become available.

6.   More details concerning all these model upgrades will be provided as they
become available.