Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1242 AM EDT Thu Mar 12 2020
Valid Mar 12/0000 UTC thru Mar 15/1200 UTC
...See NOUS42 KWNO (ADMNFD) for the status of the upper air
ingest...
12Z Model Evaluation with Final Preferences and Confidence
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...Northern stream trough tracking from the northern Rockies,
Upper Midwest toward the Northeast through Friday...
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Preference: GFS/ECMWF blend
Confidence: Slightly above average
Fairly good model agreement with the northern stream energy racing
across the Great Lakes region Thursday and Thursday night. Earlier
timing differences seem to have been resolved mostly, outside of a
slightly faster GFS/NAM solution. But these differences are fairly
minor. At the surface, the UKMET low track is displaced a bit to
the south/east of the rest of the models, and the ECMWF/GFS
continue to show very good agreement.
...Closed Low Developing Over Pacific NW Friday/Saturday...
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Preference: Non 00Z NAM blend
Confidence: Slightly above average
The 00Z NAM remains the only deterministic model that stands out
with the development of a closed low over the northwestern U.S.
for the end of the week, suggesting a deeper and slower
progression. Otherwise, the GFS/ECMWF/UKMET/CMC offer reasonable
solutions at 500 mb while at the surface, the UKMET is a touch
faster bringing the low onshore but those differences are fairly
minor. So for this cycle will continue with a non-NAM 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