Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
237 AM EDT Fri Jul 12 2019

Valid Jul 12/0000 UTC thru Jul 15/1200 UTC

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

00Z Model Evaluation Including Preference and Forecast Confidence
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...Overall Pattern Across the CONUS...
...Tropical Storm Barry...
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Preference: Non-NAM blend led by 00Z GFS/ECMWF (CONUS)
            12Z/11 ECMWF (T.S. Barry) - See latest NHC forecast
Confidence: Slightly above average

The dominant weather feature impacting the CONUS through the
short-range period will be Tropical Storm Barry which is currently
over the northern Gulf of Mexico. The 03Z NHC forecast track of
Barry is closest to the 12Z ECMWF from 07/11. The 00Z ECMWF has
trended just a tad slower and to the right of its previous run and
is now a tad slower and right of the 03Z NHC track. The 00Z UKMET
remains a westward tracking outlier, and the 00Z NAM also still
gradually takes Barry left of the NHC track, although not nearly
as far west as the UKMET. The 00Z GFS does tend to follow the NHC
track, albeit it slower. Meanwhile, the 00Z CMC is slower and
tends to be a compromise of the GFS and ECMWF.

Regarding the 00Z hires model guidance and their handling of
Barry, the 00Z NAM-conest is the closest to the NHC track, with
the 00Z ARW2/NMMB solutions notably left of the NHC track through
48 hours. The 00Z ARW is a slow outlier solution, but does tend to
otherwise follow the NHC track. Please consult the latest NHC
forecast advisory for more details on Barry.

Elsewhere across the country, there will be shortwave energy
traversing the Northwest and the northern tier of the nation
around the northern flank of a fairly strong subtropical ridge
over the Four Corners region and stretching east across portions
of the central Plains and Midwest. The 00Z NAM is perhaps just a
tad too deep and too slow with the evolution of this energy.
Meanwhile, a pair of deeper troughs will be impacting the
Northeast through the period. The model spread with these features
is modest, with the 00Z NAM perhaps just a tad too deep.

The preference for the CONUS outside of Tropical Storm Barry will
be for a non-NAM blend led by the 00Z GFS/ECMWF solutions.
Regarding Tropical Storm Barry, the previous 12Z ECMWF is the
closest solution to the NHC track.


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

Orrison