Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1157 PM EDT Fri Jun 22 2018

Valid Jun 23/0000 UTC thru Jun 26/1200 UTC

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

00Z model evaluation...including preferences and confidence 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 
...Upper low crossing the OH Valley...
...Deamplifying over the Northeast...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: General model blend
Confidence: Above average

The models are in very good mass field agreement with this system.


...Upper trough crossing the Plains/Midwest through Saturday...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: General model blend
Confidence: Above average

The models are in very good mass field agreement with this system.


...Upper trough currently moving into the Northwest...
...Amplifying into a closed low over the Intermountain West...
...Ejecting out across the Plains/Midwest Monday/Tuesday...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: Blend of the 00Z GFS and 12Z ECMWF
Confidence: Slightly above average

An upper level trough arriving across the Northwest will amplify
into a closed low on Saturday and drop drop down across the
Intermountain West through Sunday. On Monday and Tuesday, the
system will progressively eject out across the Central/Northern
Plains and the Upper Midwest. The guidance overall is in pretty
good agreement with some modest timing differences. The 00Z GFS
and the 12Z ECMWF cluster together the best, and so a blend of
these solutions will be preferred.


...Upper level trough affecting the Northeast by Monday...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: Blend of the 00Z NAM and 18Z GEFS mean
Confidence: Above average

An upper trough will amplify across the Northeast by Monday and
then evolve into a closed low near Nova Scotia through Tuesday.
The non-NCEP models led by the ECMWF, CMC and UKMET solutions all
become a bit more progressive then the NAM and GFS. However, the
NAM and GFS have both been trending a little slower and deeper.
The GFS becomes the slowest solution by Tuesday, and is a little
slower than the GEFS mean. Thinking right now that the non-NCEP
guidance is a little too progressive, and as compromise solution,
a blend of the NAM and GEFS mean will be preferred.


...Upper trough crossing the Northwest Monday/Tuesday...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: General model blend
Confidence: Above average

An upper trough will cross the Northwest on Monday and Tuesday.
The guidance is in very good agreement with their mass fields, so
a general model blend will be preferred.


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

Orrison