Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1221 PM EDT Fri Aug 10 2018

Valid Aug 10/1200 UTC thru Aug 14/0000 UTC

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

12Z Model Evaluation with Preferences and Confidence
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...Overall Synoptic Pattern across the CONUS...
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Preference: General model blend through 48-60 hours; increasingly
            weighted to 00Z ECMWF, 00Z UKMET, 00Z ECMWF Ens Mean
Confidence: Average

Models continue to be in generally better agreement, particularly
through the first 60 hours of the forecast. Agreement is better in
the western two-thirds of the CONUS, encompassing the trough
across the Northwest, the ridge building into the Midwest, and the
cutoff low in the Southern Plains. Greater differences exist with
the trough over the Northeast, particularly in the 60-84 hour time
frame of the forecast period. The 00Z CMC places the trough axis
and upper level low noticeably further east than the other models.
And the 12Z NAM and GFS now show the upper level low sinking
further south into the central Appalachians than previous runs.
The GFS, NAM and CMC are now near or just outside the ensemble
spread envelope from 00Z, and therefore are viewed as less likely
scenarios at this point.

Therefore, the overall preference is for a general model blend on
Days 1 and 2, becoming increasingly weighted toward the 00Z ECMWF,
00Z UKMET, and 00Z ECMWF Ensemble Mean on Day 3.

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

Lamers