Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
248 AM EDT Wed Jul 11 2018

Valid Jul 11/0000 UTC thru Jul 14/1200 UTC

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

00Z NAM/GFS evaluation including preliminary preference/confidence
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

...Overall Model Analysis for the CONUS...

Overall Preference: 00Z GFS/ECMWF blend
General Confidence: Average

In the wake of Hurricane Chris moving northward through the
western Atlantic, a cold front will settle into the southeastern
U.S. with perhaps a weak surface wave or two along the boundary.
There is poor agreement in the details of the weak wave but
overall the model show good agreement outside of the smaller scale
features.

A second front, currently moving through North Dakota, is expected
to continue eastward over the next couple of days with the tail
end aligning west-east across the Midwest and Plains. The 12Z/00Z
UKMET is north with this boundary for Friday and Saturday relative
to the remaining guidance and the 12Z UKMET also has a larger
mid-level ridge over the Mississippi Valley. However, the 00Z
ECMWF has trended north with the boundary as well valid Thursday
into Friday and while it does not have the anomalous ridge seen in
the UKMET, a change to include this northward shift has been
included in the preference which has lowered confidence to just
"average."

A third cold front should enter Montana ahead of an upper trough
late Friday. Only the 00Z CMC deviates from the ensemble means and
the remaining deterministic consensus with a slower reflection of
the mid-level wave, translating into a slower cold front in the
00Z CMC. There was not a large change seen in the 00Z
ECMWF/UKMET/CMC relative to their previous cycles for this system
across the Northwest through Saturday morning.


...Hurricane Chris off the East Coast...

Preference: General 00Z model blend is closest to 03Z NHC advisory

Please see the latest NHC products for the official forecast,
reasoning, and model track and intensity preferences for Hurricane
Chris.

The latest deterministic models show similar tracks for Hurricane
Chris, with the 00Z ECMWF/UKMET/CMC trending faster to near the
00Z NAM/GFS regarding timing. A blend of the 00Z deterministic
guidance is close to the official 03Z NHC forecast through at
least Thursday. Beyond Thursday, Chris is expected to transition
into an extratropical cyclone while tracking northeastward through
the open northern Atlantic Ocean.

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

Otto