Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
247 AM EDT Wed Jul 17 2019

Valid Jul 17/0000 UTC thru Jul 20/1200 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...
...Post-Tropical Cyclone Barry...
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Preference: Blend of the 00Z ECMWF/GEFS mean (Northwest)
            General model blend (elsewhere across the CONUS)
Confidence: Below average (Northwest)
            Above average (elsewhere across the CONUS)

Post-Tropical Cyclone Barry will advance quickly east across the
OH Valley and the northern Mid-Atlantic region through Thursday
and then offshore by Friday. Model spread is quite modest while
Barry is over land and merges in with a frontal zone. Thereafter,
the remnants of the system will exit quickly offshore and well out
to sea.

Going toward the end of the week and especially this weekend,
building mid-level heights are expected across much of the CONUS
with ridging extending from the Northeast back into the Southwest
states. There are some notable differences in how the models
handle troughing over the Pacific Northwest and northern Rockies
by Saturday. The 00Z UKMET is fastest with the energy and is most
out of phase with the remaining guidance. The 00Z GFS is now the
slowest solution although it has some modest support from the
12Z/16 ECENS mean. The 00Z NAM leans toward the faster side of the
guidance envelope, but is slower than the UKMET. The 00Z CMC a
little slower than the NAM, but is also the strongest solution by
the end of the period. The 00Z ECMWF is in between the GFS and CMC
solutions and actually has good support from the 00Z GEFS mean.
Based on the latest model clustering and trends, a blend of the
ECMWF and GEFS mean will be preferred over the Northwest with
below average confidence in the height fall details. A general
model blend will be preferred elsewhere over the CONUS and
especially with respect to the expansive mid-level ridge axis that
is expected to develop.

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

Orrison