Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
329 AM EDT Tue Jun 09 2020
Valid Jun 09/0000 UTC thru Jun 12/1200 UTC
...See NOUS42 KWNO (ADMSDM) for the status of the upper air
ingest...
00Z Model Evaluation Including Initial Preferences and Confidence
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...Low that spins off trough over the central Rockies and lifts
from the central Plains over the Upper Midwest Wednesday into
Wednesday night...
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Preference: General Model Blend
Confidence: Average
All 00Z guidance slowed the progression of the upper low center
that develops and traverses Kansas today. The 00Z NAM is the
deepens and thus slowest solution, but not by much. This is a
complex interaction between the trough/low and the Cristobal
remnants, so the variability can be compromised with a general
model blend given there are reasonable solutions among the
deterministic suite. The ECMWF is a little slower with the cold
front that reaches the Eastern Seaboard Thursday, but for now a
general model blend suffices.
...Cristobal Remnants...
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Preference: General Model Blend
Confidence: Average
The 00Z guidance suite provides a good, tight track window over
the next 36hrs as the remnants of Cristobal accelerate
north-northeast from south-central MO to the UP and northern
Ontario.
...Southern Gulf of Alaska Low Stalling off the BC Coast through
Thursday night...
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Preference: General Model Blend
Confidence: Average
Good agreement on Day 1 rain which is heaviest of the three days
(general onshore flow Days 2/3), but then the 00Z GFS is much more
progressive with the trough approaching the West Coast Thursday
night while the 00Z ECMWF has slowed with a closed low well off
the CA coast Thursday night. These are typical biases (GFS
progressive, ECMWF slow), so a general model blend (NAM/UKMET/CMC
are all between the ECMWF and GFS), should make for a reasonable
compromise in the middle.
Jackson
Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml