20020823: model update

• To: nws-changes@xxxxxxxxxxxxxxxx
• Subject: 20020823: model update
• From: Linda Miller <lmiller@xxxxxxxxxxxxxxxx>
• Date: Fri, 23 Aug 2002 09:44:37 -0600

MEMORANDUM FOR:   Distribution E

FROM:             John H. Ward
                 Chief, Production Management Branch

SUBJECT:          Changes to the NWS Production Suite



    The implementation of the T254 Global Forecast System (GFS)
has been rescheduled for Tuesday, 29 October.  The T254 GFS
requires approximately 20 additional minutes of wall-clock time
than the current T170 version.  The impact of this change on the
NCEP production schedule will be as follows:

      GFS 120 hour products delayed 21 minutes
      GFS 384 hour products delayed 21 minutes
      GFDL Hurricane model delayed 25-30 minutes
      Wave model products delayed 25 minutes
      AVN MOS products delayed 21 minutes
      1200 UTC Global Ensemble products delayed 25 minutes

    When the next NCEP Central Computer System becomes
operational in 2003, product delivery will return to the current
schedule.

    Details of the upcoming change to the GFS can be found at:

       http://sgi62.ncep.noaa.gov:8080/tpb97/TPB02/html/v1.html

    The GFS naming convention has created a degree of confusion
over the last few weeks.  The GFS is not a new model, it is just
new terminology for the Aviation (AVN) Model run.  Plans are
being developed to replace the AVN acronym on the WEB and in the
ftp server file structures.  Those changes, however, will occur
slowly over a lengthy period of time, with ample notification and
overlapping to provide sufficient time for the transition.  No
changes are expected prior to the completion of the Central
Computer System (CCS) conversion.

    The transition to the next NCEP CCS has began on a small,
single node test system.  Production Management Branch (PMB) has
begun to move all operational codes and scripts to the test
system and perform an initial recompile and test of the
operational codes.  Individual programmers will only be contacted
if problems are encountered during these initial tests.  At this
time production codes have not been frozen.  In early October,
all operational codes will be frozen while PMB establishes
parallel operations on the CCS.  The moratorium on changes to the
production suite can be expected to extend at least through the
normal holiday moratorium period.  Users should have their JIF's
submitted to PMB by 1 September if they want them implemented
before the moratorium begins.  No implementations will be
scheduled for October, with the exception of the T254 GFS.  More
details on the transition and moratorium will be provided as they
become available.

    A list of the major model implementations planned for 2002
can be found at:

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

    As additional information about each implementation becomes
available, links will be added on the change summary page.