Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1246 PM EDT Tue Oct 08 2019

Valid Oct 08/1200 UTC thru Oct 12/0000 UTC

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

08/12Z Model Evaluation with Preferences and Forecast Confidence
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...Energy amplifying over Central Appalachians/Mid-Atlantic...
...Deepening surface low pressure off the East Coast...
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Preference: 08/00Z ECMWF and 08/12Z GFS
Confidence: Average

The 12Z suite of NCEP guidance showed a trend towards a somewhat
deeper, broader solution with respect to the low deepening off the
northeast U.S.  This placed the NCEP guidance close the ECMWF/CMC
after they backed away from the deeper solutions they offered on
Monday.  This also put the NCEP guidance in better agreement with
the ECMWF ensemble mean from overnight.
The deeper solutions appear to have the greatest deep
convection/latent heat influence and given the strength of the
moisture feed, there is growing confidence toward this evolution.


...Deep upper trough/closed low amplifying over the West...
...High Plains cyclogenesis...
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Preference: General model blend
  After 11.00z: Lower weight in the GFS 
Confidence: Above average

Models continue to show very strong agreement with the evolution
of the deep latitude, positive tilt trof through about
10.00z...with the agreement being strengthened by the adjustments
made by the ECMWF at the 08/00Z.  The 12Z GFS maintained a slower
solution given a more compact evolution to the deepening low into
the Central Plains. With stronger overall agreement in the NAM,
UKMET, CMC and the slowing of the GFS...it is harder to have
confidence in higher weighting in the blend.   So WPC preference
is a general model blend with above average confidence before
72hrs.   After 72hrs (11.00z), WPC preference would be to still be
a general model blend but lower weighting to the operational ECMWF
and GFS. 


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

Bann