Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
122 AM EDT Fri Oct 12 2018

Valid Oct 12/0000 UTC thru Oct 15/1200 UTC

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

00Z Model Evaluation...with latest preferences and confidence
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

...Overall Pattern Across the CONUS... 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: Blend of the 11/12Z ECMWF/UKMET and 12/00Z NAM
Confidence: Average

The general pattern across the CONUS will feature a longwave
trough amplifying over the central/western US, with a broad, flat
ridge that develops late in the weekend over the Eastern U.S.
following the passage of a shortwave trough today and Saturday. A
high amplitude ridge should be anchored over the eastern North
Pacific Ocean that noses up into British Columbia through early
early Monday morning.

There is good model agreement on the frontal passage across the
Mid-Atlantic and Northeast US today with high pressure building in
across the Central Plains.  However, the model agreement is not as
strong with respect to shortwave energy dropping into the Upper
Midwest.   Based on the latest model spread and clustering of
solutions across the continental U.S. for this period, combining
elements of the 12.00Z NAM and the 11/12Z ECMWF/UKMET should be a
good starting point that captures the essence of the large scale
flow pattern while addressing differences in timing through Day 2.
 However, the UKMET becomes a noticeable outlier beginning late
Saturday night which makes its use questionable. 

...Tropical Storm Michael...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: See the latest NHC forecast advisory

There is good clustering in the global models that show Michael
exiting off the Mid-Atlantic coast through the day on Friday.

...Hurricane Sergio...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Preference: See the latest NHC forecast advisory

The 12/00Z runs of the NAM and GFS and the 11/12Z UKMET are close
to the NHC track through the day today.  Beyond that, the global
models tend to lose a surface reflection as Sergio crosses the
mountains of northern Mexico. although the GFS still maintained a
850 mb relative vorticity center that was close to the NHC track
into New Mexico.


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

Bann