Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1243 PM EDT Tue Sep 10 2019

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

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

12Z Model Evaluation with Initial Preferences and Forecast
Confidence
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...Overall Pattern Across the CONUS...
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Preference: General model blend, strongest weights to...
            10/00Z ECMWF, 10/00Z GEFS Mean, 10/12Z GFS
Confidence: Average

---PREVIOUS DISCUSSION---
Models continue to show signs of converging on a consistent
solution over the past couple model cycles, and are now in
reasonably good agreement on the synoptic pattern over the next
few days. The deterministic models and ensemble members are
tightly clustered with their mass field forecasts as a trough
pushes through the West over the next couple days, with some more
spread emerging...especially by Thursday evening (13.00Z).

The 10/12Z GFS and 10/12Z NAM show the more substantial departures
from ensemble means out of the available deterministic models, but
are still generally supported by the full ensemble distribution as
reasonable possibilities. Furthermore, their QPF is similar in
many respects to the ensemble means and other global models.

Therefore, a broad model blend is the preference, with slightly
less weight on the latest NAM, and greater weight on the ECMWF and
the ensemble means, which have been more consistent. With the
tendancy for ensemble means to be too weak, a blend which includes
at least some GFS would help offset that tendancy.


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

Bann