Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
340 PM EDT Mon Jul 01 2019

Valid Jul 01/1200 UTC thru Jul 05/0000 UTC

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

12Z Model Evaluation...with Final Confidence and Preferences
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

...NOTE: The 12Z ECMWF was only available through F048 hours
(12Z/03) at the time of this discussion. Therefore, preferences
including the 12Z ECMWF only include a limited time span of the
short range period.

...Overall Pattern Across the CONUS...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: General model blend, led by the 00Z/12Z ECMWF and 12Z
GFS
Confidence: Slightly below average

...19Z update...

Changes in the 12Z ECMWF (through 12Z/03) and the 12Z UKMET/CMC
were minor compared to their previous 00Z cycles. No changes
regarding model preferences are recommended other than replacing
the 00Z ECMWF with the 12Z ECMWF.

...previous discussion follows...

The synoptic scale pattern over the lower 48 through Thursday will
be relatively stagnant with mid-upper level troughing over the
Northwest, with ridging centered over the Gulf of Mexico. At the
surface, a relatively strong cold front will move into the Dakotas
on Tuesday with stalling for Wednesday and Thursday. South of this
boundary, weak mid-level impulses will track northeastward from a
weak and nearly stationary mid-upper level low/trough axis
situated over the central to southern Plains.

The 00Z UKMET/CMC show a greater degree of mid-level ridging over
the eastern 2/3 of the nation through the middle of the week than
other available guidance. The 12Z NAM remains faster with its
progression of mid-level shortwaves across the Midwest into the
Great Lakes region Wednesday and Thursday with better support for
a non-NAM blend across this area of the nation. Ensemble
clustering is best suited to a general model blend as a whole, led
by a blend of the 00Z ECMWF and 12Z GFS. The usual detail
differences given summertime convection will remain which keeps
confidence a bit lower than average.

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

Otto