Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
109 PM EDT Thu Jun 13 2019

Valid Jun 13/1200 UTC thru Jun 17/0000 UTC

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

12Z Preliminary Model Evaluation...with Confidence and Preferences
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...Overall CONUS Overview...
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Preference: General model blend, except for the north-central U.S.
where a non-12Z GFS blend is recommended
Confidence: Average

The pattern across the lower 48 through Sunday will feature a slow
moving closed low in southeastern Canada with two main pieces of
energy while the central and western U.S. will be dominated by
weak northwest flow containing a few embedded shortwaves. No
single model stands out as unusable except for the 12Z GFS across
the north-central U.S.

There is strong agreement for a weak shortwave currently along the
British Columbia coast to merge with a small vorticity max to its
north over Alberta and Saskatchewan on Friday and Saturday,
resulting in a somewhat broad mid-upper level trough over the
north-central U.S. for Saturday/Sunday. The 12Z GFS was
significant weaker with this trough noted on Saturday over Montana
and North Dakota compared to the remaining deterministic model
consensus and while not an outlier with respect to the ensembles,
will not be preferred given a lack of support. Run to run
consistency has been fairly good with this feature in all of the
models.

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

Otto