Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1252 AM EDT Wed Jul 10 2019

Valid Jul 10/0000 UTC thru Jul 13/1200 UTC

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

00Z Model Evaluation Including Preference and Forecast Confidence
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

...Overall Pattern Across the CONUS...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: General model blend (Northern Plains to Northeast)
            Blend of the 00Z GFS and 12Z CMC/ECMWF (Gulf Coast
States)
            Blend of the 00Z GFS and 12Z ECMWF (Pacific Northwest)
Confidence: Slightly above average

Through the next 3 days, there continues to be reasonably good
agreement with the synoptic pattern across the CONUS. Shortwave
energy will trek across the Great Lakes and into the Northeast
U.S. while a ridge builds and retrogrades to the Four Corners
region. Tropical development in the north central Gulf of Mexico
will be dictated by the strength/position of the western ridge
over the coming days. Finally, another piece of shortwave energy
will approach the northwest U.S.

For the northern tier of the U.S., a general model blend can be
applied where the above average similarity in the mass fields and
surface patterns. The biggest differences lie with the potential
tropical development along the Gulf coast. For now, the 12Z UKMET
is considered an outlier as it is 1) too far west and 2) too deep
compared to the rest of the model guidance and ensemble spread.
The NAM is also considered an outlier as it is too fast and also
too far west. There is good clustering with the latest
GFS/ECMWF/CMC, which is the preferred blend at this time for the
feature.

Otherwise, the guidance does support a reloading upper trough
offshore the Pacific Northwest by the end of the period. The 12Z
NAM is the slowest and deepest with this solution, with the 12Z
UKMET the fastest. Overall, the 12Z CMC is now the weakest
solution, but is not as fast as the UKMET. The 12Z GFS and 12Z
ECMWF are now the best clustered in between slower and faster
camps, and with a reasonable depth that is supported by the 12Z
GEFS mean and 00Z ECENS mean. Based on this, a blend of the GFS
and ECMWF will be preferred for the energy offshore the Pacific
Northwest toward the end of the period.


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

Taylor