Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1245 PM EDT Tue Sep 04 2018

Valid Sep 04/1200 UTC thru Sep 08/0000 UTC

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

12Z model evaluation...with latest preferences and confidence 
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...Overall Synoptic Pattern across the CONUS...
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Preference: General model blend, weighted toward 00Z ECMWF
Confidence: Slightly above average 
 
The model mass field differences were fairly small over the next
several days across the CONUS, and individual deterministic models
are contained well within the total envelope of ensemble spread.
Therefore, a general blend was the overall preference. The 12Z GFS
did show a faster southeast progression with its rainfall over the
Midwest relative to the other models, and the 06Z GEFS Mean, so
less weight was placed on the GFS there. Overall, greater weight
was placed on the 00Z ECMWF for the WPC QPF.


...Tropical Storm Gordon...
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Preference: Please consult the latest NHC forecast
 
The 00Z ECMWF and 12Z NAM were slightly closer to the NHC forecast
track for Gordon, although all of the models were fairly close.
Therefore, greater weight was placed on the ECMWF, NAM, and GEFS
Mean for the WPC QPF in this region, with the incorporation of
some hi-res models for detail in the first 24 hours or so. Please
see the National Hurricane Center products for overall forecast
and confidence information regarding this tropical cyclone.


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

Lamers