[Vis5d-users] Re: Grib Question

Michael:

Since 1997 NCEP/EMC produce Vis5D files of the
NCEP models on a timely basis for a number of
preset areas and variables.  While this is done for
my own account, there is no restriction on public use of these
files.  You may find access to them on the web page:

http://sgi62.wwb.noaa.gov:8080/research/vis5d.html

The Vis5D files are created automatically and unattended.
A short (rotating) archive is maintained for each of the
entries.   For example, the Medium Range Model (run once
a day at 00Z) over an area containing North America
maintains the last 4 cycles (days) of runs and the most
recent.  2 of the 4 Eta run cycles are available per day
going back for three days (6 model runs).  The   date/cycle is
part of the Vis5d file name.

The ensembles (of many model integration's) are Vis5D
files with the vertical coordinate as the ith component of the
ensemble run instead of elevation, z.  One can use vis5d
to sweep through all the ensembles at any time or look
at Vis5D Iso-surfaces which give weather event probability
for user selected events.

There are contributions from the operational (and other)
regional RUC, Eta, NGM and the Global models
as well as some reruns of special cases,
for example, the Storm of the Century:

http://sgi62.wwb.noaa.gov:8080/JAEMC1/eta_century/CEN_ETA930212.v5d

A Pacific Typhoon:
http://sgi62.wwb.noaa.gov:8080/JAEMC1/paka/PAKA_971210.v5d

The Perfect Storm
 http://sgi62.wwb.noaa.gov:8080/JASGI100/gemvis/perfect_storm/PRSTM1027.v5d

There are also difference files like forecast error and and differences
between experiments and operational runs.

These files use GEMVIS (available on the same Vis5d web site)
which links with GEMPAK (see the Link to the Unidata site) to
conveniently create the Vis5D files from the model run history
(GRIB) files.  The Vis5D files typically contain the standard run
history elements of T, RH, moisture, TD, U, V, W, (for the skew-T)
Vort., Div. and a number of advective quantities such as vorticity,
moisture, temperature and many 2-D fields such as PRCP
(convective and large scale) surface T, and precip water.
I have tried to keep the file size range between 10-50Mb.

The process of improving our ensembles, reconnecting
the 10km Hawaii run and other systems turned off when
NCEP switched computers are where things stand now.

Jordan Alpert



Michael Maxwell wrote:

> Does the NCEP produce data for Vis3D? Like the ETA and NGM.