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Model Diagnostics Discussion
(Caution: Version displayed is not the latest version. - Issued 0413Z Aug 16, 2018)
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Geographic Boundaries -  Map 1: Color  Black/White       Map 2: Color  Black/White

Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1213 AM EDT Thu Aug 16 2018

Valid Aug 16/0000 UTC thru Aug 19/1200 UTC

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

00Z Model Evaluation...with Preferences and Confidence

...Overall Synoptic Pattern across the CONUS...
Preference: Blend of 12Z ECMWF, 00Z GFS
Confidence: Slightly above average

In the next several days, the pattern will feature relatively
progressive troughs pushing across the northern half of the
country, with a relatively steady subtropical ridge slowly
retrograding from the southern Plains into the Southwest. Models
are in fairly good agreement overall on the pattern. The largest
differences are with the trough evolving over the Northeast this
weekend; the 00Z NAM and 12Z UKMET are out of phase with the other
deterministic models and ensemble means, and therefore they are
not preferred. The 12Z CMC also shows some differences with a
deeper trough in the Northeast, despite being more in phase with
the other models. In fact, its heights are lower than a lot of the
available ensemble members. Therefore, the preference is for a
blend of the GFS and ECMWF, as they show the most consistency and
are closest to a consensus of the ECMWF and NAEFS ensemble means
with their mass fields. Other models could be incorporated into
the forecast, particularly outside the Northeast region, but the
preference is for the greatest weight on the GFS and ECMWF.

Model trends at
500 mb forecasts at