Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
122 AM EST Sun Nov 03 2019

Valid Nov 03/0000 UTC thru Nov 06/1200 UTC

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

...00Z Model Evaluation with Preferences and Confidence...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
...Overall Pattern Across the CONUS...

Preference: General model blend
 Exception: Remove 00z GFS in Plains after 06.00z
Confidence: Above average

07z update: A slight shift/tightening of the inverted surface trof
across the Central Plains in the 12z GEFS aligned better with the
ECMWF/NAM and ECENS mean suggests the slower 00z GFS is on the
outer fringe of consensus to remove it across the Plains after
06.00z.  Otherwise, the ECMWF, CMC and UKMET show solid
consistency.  There is some small timing differences across the
Northern Plains/Boundary waters of MN by the end of Day 3, but a
general blend (with exception of the GFS) remains warranted at
above average confidence.

---Prior Discussion---
Model agreement on the overall synoptic pattern remains very
strong, including the 00z GFS/NAM deterministic models generally
within a narrow envelope of ensemble spread. There are some
important very small scale detail differences, primarily with
shortwaves moving through the stronger flow at the base of a broad
global scale trough from the Northern Plains, Great Lakes, into
the Northeast. This affects the placement of some areas of
precipitation -- including one swath in the Upper Midwest on
Sunday Night and Monday, and another near the Northeast coast on
Tuesday. In general, the placement of areas of precipitation was
near a median position of the available models, given a lack of
identifiable bias from any individual models and the very minor
differences in the mass fields overall.  In the Southwest, a
closed low will be developing in the vicinity of the California
Bight, slowly dropping south.  By early Wed, the upstream ridge
breaks down a bit, allowing for northern stream energy to dip
south enough to start pulling the closed low northeastward.  The
00z GFS has slowed this process, having been the fastest ejecting
back into the stream and now matching the ECMWF, UKMET, CMC and
ensemble suite.  The 00z NAM is slower as well, but is a bit
faster lifting out, breaking from stronger consensus.  However,
this is fairly small.   So overall, a general model blend can be
supported at above average confidence.


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

Gallina