Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1125 PM EST Tue Feb 11 2020
Valid Feb 12/0000 UTC thru Feb 15/1200 UTC
...See NOUS42 KWNO (ADMNFD) for the status of the upper air
ingest...
00Z Model Evaluation with preferences & confidence
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Overall Pattern Across the CONUS
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Preference: General model blend through day 2 (14.00Z), then
non-NAM day 3
Confidence: Average
Phasing of southern stream energy from the weakening/opening
closed low over the Southwest and Southern Plains and a energy
coming the Canadian Rockies will act to deepen troughing over the
eastern 2/3 of the CONUS in the next couple of days. Meanwhile,
ridging aloft is expected to break down toward day 2 as another
shortwave trough quickly moves across the Pacific Northwest. The
bulk of that energy is likely to remain in the northern stream
though a piece is forecast to break off and eventually form a
meandering closed low around Baja toward day 3. The latest
guidance shows favorable agreement across the CONUS particularly
through 48 hours (14.00Z) such that a general model blend would be
more than sufficient for mass field purposes. Beyond that time
frame, the NAM becomes a bit too amplified east of the Rockies
with the troughing over the eastern US, as well as much slower
compared to the rest of the guidance. As such, it was considered
an outlier for day 3 and was not included in the preferred blend.
Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml
Taylor