Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
256 AM EDT Thu Jul 11 2019

Valid Jul 11/0000 UTC thru Jul 14/1200 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...
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Preference: General model blend (across the CONUS)
            See latest NHC advisories for P.T.C. TWO (Gulf Coast)
Confidence: Slightly above average

Over the next 3 days, there continues to be reasonably good
agreement with the synoptic pattern across the CONUS. Shortwave
energy will track across the Great Lakes and into the Northeast
U.S. while a ridge builds and retrogrades to the Four Corners
region. Tropical development is anticipated across the northern
Gulf of Mexico, and the NHC was issuing advisories on Potential
Tropical Cyclone Two (P.T.C. TWO). The track of this system will
be dictated by the strength/position of the strengthening ridge to
the north and west of the cyclone. Elsewhere, there will be a new
shortwave trough impacting areas of the Pacific Northwest, but the
bulk of the height falls are expected to remain offshore.

For the northern tier of the U.S., a general model blend can be
applied where the guidance is well clustered with timing and depth
of the shortwave trough evolution.  That includes the system
moving into the Pacific Northwest.

The biggest model differences continue to revolve around P.T.C.TWO
over the northern Gulf of Mexico.  The NAM and UKMET remained on
the western side of the guidance...a position that both models
have maintained for multiple model runs.  Of those two pieces of
guidance, the NAM was fastest.  The UKMET definitely had a much
stronger subtropical ridge building north of the system through
the period which is aided its farther west track.

At the same time, the 00Z GFS was the becomes is the slowest
solution and supports a recurvature up across southeast LA by
early Saturday. The ECMWF had largely maintained continuity
through Day 3, while the 00Z Canadian changed its thinking and was
now closer to the GFS idea.  The 00Z ECMWF remained closest to the
03Z NHC forecast track and supports a direct impact across
southwest to south-central LA by midday Saturday. Please consult
the latest NHC forecast advisories/discussions for more details on
P.T.C. TWO.

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

Bann