Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1244 AM EDT Tue Aug 28 2018

Valid Aug 28/0000 UTC thru Aug 31/1200 UTC

...See NOUS42 KWNO (ADMNFD) for the status of the upper air
ingest...

00Z GFS/NAM Model Evaluation with Preliminary Preference and
Confidence
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...Overall Synoptic Pattern across the CONUS...
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Preference: Non-NAM Blend
Confidence: Slightly Above Average

One medium wavelength trough will lift through the Upper Midwest
and into eastern Canada, dragging a cold front into the
central/eastern United States. Another medium wavelength trough
shift east over the northwest.

Models are generally in good agreement on the movement and
evolution of these large scale features through 31/12Z. The
solutions are clustered well enough that a blend of the
operational models is recommended. The exception is the 00Z NAM
which is more amplified with the trough in the east vs the
consensus by Wednesday night. This suppresses the cold front over
the eastern US which makes for less precipitation up the
northeastern coast for Day 3. Otherwise, the agreement with the
00Z GFS with other 12Z guidance is notable through the short term
forecast period.

Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml

Jackson