Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
239 AM EDT Wed Oct 17 2018

Valid Oct 17/0000 UTC thru Oct 20/1200 UTC

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

00Z Model Evaluation...with latest preferences and confidence
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...Closed low initially over the Desert Southwest...
...Amplified flow crossing the northeastern U.S. on Wednesday...
...Renewed troughing across the Great Lakes by early Saturday...
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Preference: General model compromise, except non-21Z SREF mean
with the southwestern U.S. closed low
Confidence: Above average

Generally speaking, the global models are in solid short range
agreement across the nation. However, there is one area of
uncertainty to note which is the closed low evolving into an open
wave across the Four Corners on Thursday. The 21Z SREF mean is a
slow outlier fairly early in the period with this feature.
Otherwise, the guidance exhibits good clustering with the
amplified trough exiting the Northeast as well as the potent
height falls swinging into the north-central U.S. late in the
week. Ensemble spaghetti plots remain consistent with this latter
system with operational model spread minimal.



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

Rubin-Oster