Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1113 AM EST Mon Feb 10 2020
Valid Feb 10/1200 UTC thru Feb 14/0000 UTC
...See NOUS42 KWNO (ADMNFD) for the status of the upper air
ingest...
12Z GFS/NAM Evaluation with model preferences & confidence
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
There do not seem to be GFS/NAM initialization issues which
degrade their forecasts.
Trough dropping into the Great Lakes Wed/Thu
Trough over the Great Basin/Southwest Mon/Tue & southern Plains Wed
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: Non-GFS compromise
Confidence: Above average
The 12z GFS, while trying to shear the system out/open the system
up aloft through the Southern Plains into the Mid-South, somehow
strengthens 500 hPa vorticity within what should otherwise be a
weakening/elongating system. This lures the GFS upper trough in
the Great Lakes Wed/Thu eastward/quicker despite a stronger and
slower mid-level ridge upstream across the Prairie Provinces of
Canada. Would lean away from the 12z GFS with these systems with
above average confidence.
Elsewhere across the Lower 48
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Differences amongst the guidance are well within the noise with
other systems moving across the lower 48. Prefer a compromise of
the available guidance there with above 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
Roth