Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
229 AM EDT Sun Jun 24 2018

Valid Jun 24/0000 UTC thru Jun 27/1200 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 trough exiting the Northeast overnight...
...Upper trough crossing the OH Valley through early Sunday...
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Preference: General model blend
Confidence: Above average

The models are in very good mass field agreement with both of
these systems.


...Amplifying closed low over the Intermountain West...
...Ejecting out across the Plains/Midwest Monday/Tuesday...
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Preference: General model blend...through 72 hours
            Non-UKMET blend...after 72 hours
Confidence: Above average

The models are in very good mass field agreement with this system
as it ejects out of the West and crosses the Plains and Midwest
through most of the period. However, the 00Z UKMET does appear to
be a little too strong with its surface low lifting up across the
upper Great Lakes region by the end of the period. Will prefer a
general model blend through about 72 hours, and then a non-UKMET
blend thereafter.


...Upper level trough affecting the Northeast by Monday...
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Preference: General model blend...through 60 hours
            00Z GFS...after 60 hours
Confidence: Slightly above average

An upper trough will amplify across the Northeast by Monday and
then evolve into a closed low near Nova Scotia through Tuesday.
The 00Z UKMET and 00Z ECMWF are the strongest solutions, and
especially as the height falls cross near the Canadian maritimes.
These model have a stronger surface low reflection as well. The
remaining guidance is a tad weaker and the slightly weaker
consensus does have a bit more ensemble support, especially from
the GEFS members. The 00Z CMC though appears to be too slow. Will
prefer a general model blend through 60 hours, followed by a
solution weighted closer to the 00Z GFS thereafter as it is quite
close to the model consensus.


...Upper trough crossing the Northwest Monday/Tuesday...
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Preference: General model blend
Confidence: Above average

An upper trough will cross the Northwest on Monday and Tuesday.
The guidance overall is in good agreement with their mass fields,
with only very modest timing/depth differences, so a general model
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