Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
238 AM EDT Thu Aug 30 2018

Valid Aug 30/0000 UTC thru Sep 02/1200 UTC

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

00Z model evaluation with final model preferences and confidence
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...Overall Synoptic Pattern across the CONUS...
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Preference: Blend of the 00Z GFS, 00Z UKMET and 00Z ECMWF
Confidence: Slightly above average

The large scale upper pattern will feature a series of progressive
shortwaves advancing across southern Canada and the northern tier
of the U.S. through the short range period, with the general
tendency for a mean layer trough to focus over the Intermountain
West and a rather strong mid level subtropical ridge to remain in
place over the southern and eastern U.S.

The 00Z ECMWF trended a little weaker with the troughing that
should drop into the southwestern U.S. and is now very close to
the model consensus with these height falls. The 00Z NAM and 00Z
CMC though are more out of tolerance relative to the 00Z GFS, 00Z
UKMET and 00Z ECMWF across the south-central Canada. Elsewhere,
the NAM was noted to be by far the strongest with an easterly wave
moving across the northwest Gulf of Mexico by Saturday, which in
the case of the NAM supports a rather strong convective low. The
NAM will again be discounted given a strong lack of support.

Based on the latest clustering of solutions, a preference toward a
blend of the 00Z GFS, 00Z UKMET and 00Z ECMWF will be preferred
for now across the CONUS and this has support from the 00Z GEFS
mean and the 12Z ECENS mean.

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

Orrison