FROM: John H. Ward
1. The resolution increase of the GFS from T254 to T382 has been
scheduled for 12Z on 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 sample data set from the T382 parallel runs can be obtained from the following
location:
ftp://ftpprd.ncep.noaa.gov/pub/data1/t382/gfs.20050504
The size of the surface flux files for forecast hours 00 to 180 will increase to
44 MB each and for forecast hours 192 to 384 they will increase to 11 MB each.
A few 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 discrete 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.
C. Convective cloud heights will no longer be available for the analysis time
period.
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