Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
345 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 Model Evaluation with 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 through Thursday night. Another
medium wavelength trough shifts east over the northwest through
this time, though this is of little precipitation consequence.

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 in
the east which is more amplified with the trough vs 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, only minor differences are apparent in
placement of the front/precipitation through Thursday night. The
00Z ECMWF is a bit farther north with the front in the east than
the 12Z which was a bit north of the rest of the global guidance.
Should the ECMWF continue to trend north, it may be dropped from
the preference.

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

Jackson