Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1259 AM EDT Mon Jun 18 2018

Valid Jun 18/0000 UTC thru Jun 21/1200 UTC

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

12Z Model evaluation including preferences and forecast confidence
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...Overall model diagnostic analysis for the CONUS...
......exception(s) in section(s) below......
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Preference: Non-GFS blend
Confidence: Above average thru 20/00z...average afterward

Overall, the 00Z NCEP guidance continued to show good agreement in
their large scale flow pattern over North America through about
20/00Z, including placement and timing of shortwave energy moving
out of the Rockies and into confluent flow downstream.  In
addition, there was generally good agreement with flow over the
eastern part of North America.

Some of the concerns from earlier about the 17/12Z GFS run are
still in play in the 18/00Z run.  The closed low initially over
the Great Basin area begins to break down and slide southeast. 
The amount of upstream ridging depicted by the GFS...which has
implications on the placement of the weakening downstream
closed-low...is an outlier solution.  At this point, WPC is not
inclined to include the GFS in a general-model blend. 


...Broad TUTT Cell and low level easterly tropical wave
progressing through Western Gulf
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Preference: 17/12Z ECMWF/CMC blend
Confidence: Below average

Large model spread remains both in the deterministic guidance and
internal ensemble members with respect to the development of this
TUTT and surface wave. 

The 50 member ECENS suite showed a large variety of potential
outcomes.  Much like the previous model diagnostician, think that
in all likelihood that none as consolidated/robust as the UKMET
and very few near the operational EC.   The 00Z NCEP guidance
still tends to suggest a much stronger ridge over Mexico as well
as over the Eastern Gulf with increased energy shed to the
northern stream.  This still leaves the 17/12Z CMC on the slow
side of the solution with the 17/12Z ECMWF.

Overall the trend continues to tip toward a stronger/deeper more
consolidated response, but not as dramatic as the ECMWF or UKMET. 
As such a preference toward the 17/12Z EC/CMC solutions is
preferred at below average confidence.

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

Bann