Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1249 AM EDT Fri Jul 26 2019

Valid Jul 26/0000 UTC thru Jul 29/1200 UTC

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

00Z NAM/GFS Model Evaluation, Including Preliminary Confidence and
Preferences
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...Northern Tier of the U.S...
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Preference: 12Z ECMWF/00Z NAM/12Z CMC blend
Confidence: Average

Two shortwaves will track across southern Canada from west to east
through Sunday night. The first shortwave entering Manitoba early
this morning shows no significant differences as it tracks into
Ontario and Quebec over the weekend. The timing has gotten better
regarding a second shortwave to enter Saskatchewan Saturday night
compared to yesterday's guidance. While timing of this second wave
has gotten better, the 00Z GFS is weak with a mid-level vort and
low level wave to the south of the Canadian shortwave over the
Dakotas. The 12Z UKMET is slightly quicker than the consensus
leaving the 00Z NAM, 12Z ECMWF and 12Z CMC is good agreement with
the ensemble means while carrying good run to run consistency.


...Remainder of the CONUS including the Southwest...
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Preference: General model blend
Confidence: Slightly above average

No significant mass field differences were noted with the
southwestern ridge and some of the more significant vorticity
maxima revolving around the center of the ridge. Regarding the
remainder of the U.S., similarly, no significant mass field
differences were noted in the latest guidance.

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

Otto