Changes to the NWS Production Suite

• To: nws-changes@xxxxxxxxxxxxxxxx
• Subject: Changes to the NWS Production Suite
• From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx>
• Date: Fri, 18 Mar 2005 08:04:25 -0700

FROM:                   John H. Ward
                       Chief, Production Management Branch






1.      The Frost system is expected to be back in service by 15 April.  On or 
about that
date the Snow system will be taken out of service for approximately 6 weeks.  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.

2.   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 only expected 
to increase
by 0.2 MB.

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

4.   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.

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