Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1236 PM EDT Sun Mar 10 2019
Valid Mar 10/1200 UTC thru Mar 14/0000 UTC
...See NOUS42 KWNO (ADMNFD) for the status of the upper air
ingest...
12Z Model Evaluation Including Initial Preferences and Confidence
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...Positively tilted shortwave trough moving east into Manitoba
and Ontario into Monday morning...
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Preference: General model blend
Confidence: Slightly above average
Only minor timing/depth differences remain with this system. The
10/12Z NCEP runs and the 10/00Z ECMWF still had the support of the
latest ensemble means...but were faster than the 10/00Z UKMET/CMC.
A general model blend should handle these differences adequately.
...Surface low tracking north of the Great Lakes this evening
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Preference: General model blend
Confidence: Slightly above average
Differences with this system are small enough such that a general
model blend can be used.
...Large closed low forming just offshore of California Sunday
night and tracking through Arizona and New Mexico Tuesday/Tuesday
night...
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Preference: 10/12Z GFS, 10/00Z ECMWF blend
Confidence: Average
The model agreement is pretty good through the Day 2 forecast
period with respect to the track of the closed low. However,
spread opens up towards the end of Day 3 as the mid-level center
makes a curve towards the north/northeast and takes on a negative
tilt. The 10/12Z NCEP guidance was close to the solutions they
offered in previous runs, so the Canadian remained on the slower
side of the guidance. The 10/00Z UKMET was more aggressive in
lifting the center northeast into Kansas...which seems a bit too
fast. So will recommend the 10/12Z GFS and 10/00Z
ECMWF...especially given their proximity to the ensemble mean.
...Progressive upper trough approaching the Pacific Northwest
Tuesday morning...
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Preference: General model blend
Confidence: Average
The 10/00Z CMC was slower to bring a surface low to the coast of
British Columbia on Monday, much like the its previous couple of
runs, but sensible weather impacts are north of the border.
Otherwise, the deterministic and ensemble guidance shows good
agreement.
Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml
Bann