Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
229 AM EDT Fri Jun 22 2018

Valid Jun 22/0000 UTC thru Jun 25/1200 UTC

...See NOUS42 KWNO (ADMNFD) for the status of the upper air
ingest...

00Z model evaluation...including preferences and confidence
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...Upper low crossing the OH Valley...
...Deamplifying over the Northeast...
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Preference: General model blend
Confidence: Above average

The models are in very good mass field agreement with this system.


...Upper trough crossing the Plains/Midwest through Saturday...
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Preference: General model blend
Confidence: Above average

There is only very modest mass field spread with this system, so a
general model blend will be preferred.


...Upper trough arriving across the Northwest on Friday...
...Amplifying into a closed low over the Intermountain West...
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Preference: Blend of the 00Z GFS and 00Z ECMWF
Confidence: Slightly above average

An upper level trough will arrive across the Northwest by Friday
and amplify into a closed low on Saturday which drops down across
the Intermountain West through Sunday. The 00Z NAM tends to be a
little stronger than the global models with this system. The 00Z
CMC becomes a bit of a slower outlier. The 00Z GFS and 00Z ECMWF
cluster overall the best and approximate the model consensus, so a
blend of the GFS and ECMWF will be preferred.


...Upper level trough affecting New England by Sunday...
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Preference: General model blend
Confidence: Above average

The models are in good mass field agreement with this system.


...Upper trough digging into the Northwest by Monday...
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Preference: Non-NAM blend
Confidence: Above average

The 00Z NAM is a little slower and sharper than the global models
with the trough digging in across the Northwest by Monday. The
global models though are very well clustered on timing and depth,
so a non-NAM blend will be preferred.


Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml

Orrison