Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1229 AM EDT Sat Jul 14 2018

Valid Jul 14/0000 UTC thru Jul 17/1200 UTC

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

12Z Model Evaluation...with Preliminary Preferences and Confidence
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

...Overall Model Analysis for the CONUS...

Overall Preference: Blend of 00Z GFS; 12Z ECMWF; 12Z UKMET
General Confidence: Slightly above average

The pattern over the CONUS over the next few days will generally
be dominated a large upper level anticyclone and weak flow, but a
trough will be digging into the Great Lakes and Northeast by early
next week. Models continue to be in fairly good agreement overall
on the mass fields, generally giving high confidence in the
synoptic pattern. However, typical summer QPF uncertainty will
exist due to the overwhelmingly convective nature of the rain.

Two models showed some differences worth noting. First, the 00Z
NAM shows some stronger shortwaves relative to other models: in
the Midwest today, and moving into the West Coast on Sunday. This
is a typical bias. Second, the 12Z CMC shows a flatter and weaker
wave moving into the West Coast. The preference, therefore, is to
exclude these models from the recommended blend, although in other
areas they could be reasonable enough to include in the forecast.


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

Lamers