Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
306 AM EDT Tue Jul 07 2020
Valid Jul 07/0000 UTC thru Jul 10/1200 UTC
...See NOUS42 KWNO (ADMSDM) for the status of the upper air
ingest...
00Z Model Evaluation with Model Preferences/Confidence Intervals
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NAM/GFS initialization errors do not seem to degrade their short
range forecasts.
New trough moving into the Pacific Northwest Thursday
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Preference: Model Blend
Confidence: Slightly above average
The guidance shows general agreement with the depth and
progression of this feature into Thursday evening, although the
00Z GFS was a bit deeper and quicker than the 00Z ECWMF. Given
the model agreement, a blend should result in a consistent
large-scale picture while minimizing some of the minor timing
differences.
Closed low moving east along the western & central US/Canadian
border
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Preference: Non-NAM compromise
Confidence: Slightly above average
The guidance shows good agreement with this feature moving east
from the Pacific Northwest through later tonight before the 00Z
NAM becomes a slow/deep outlier in south-central Canada -- much
like it did in the 12Z model cycle. Since the flow pattern in
which it is embedded is fairly zonal, will prefer a compromise of
the latest GFS/ECMWF and Canadian with slightly above average
confidence.
Deep layer cyclone edging east-northeast near the VA/NC border
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Preference: Model Blend
Confidence: Above average
A deep layer cyclone is expected to move slowly east-northeast as
a mid-level ridge builds to the north across the northern
Appalachians and New England. A progressive ridge moving over the
top of the system argues for favoring a solution on the slower
side of the guidance. Still prefer a compromise of the latest
GFS/NAM/UKMET with above average confidence.
Shortwave trough moving by New England Wednesday
Weakening 700 hPa trough across NV/CA through Thursday
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The guidance shows good agreement with the progression and depth
of these features, so prefer a compromise of the 00Z NAM, 00Z GFS
and the 00z ECMWF with above average confidence.
Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml
Bann