Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1136 AM EST Mon Feb 05 2018

Valid Feb 05/1200 UTC through Feb 09/0000 UTC


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

12Z NAM/GFS evaluation with preliminary model preferences
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Initialization errors in the NAM/GFS do not seem to degrade their
short range forecasts.


Upper trough weakening as it moves out of the Southwest
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: Non-NAM compromise; Confidence above average

The 12z NAM is a little more amplified aloft with the upper trough
in the Southwest which allows it to drag eastward into Texas as a
stronger feature on Wednesday.  Overall, a broad trough exists
over North American with a strong mid-level reflection of the
Polar Vortex across northwest Quebec.  This should force the
system to eject out relatively flat, eliminating the NAM from
consideration.  This is important in the model instability fields
across TX as well as QPF pattern across the southern Plains, lower
MS valley, and Mid-South.  See the QPF discussion for more details
on the precipitation forecast.


Shortwave moving towards the Northwest Thursday
Shortwave moving across New England Tuesday
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The guidance is within reason with these systems.  A compromise of
the 00z Canadian, 00z ECMWF, 00z UKMET, 12z NAM, and 12z GFS
should work out well with above average confidence.


Roth

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