Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
1241 PM EDT Sat Jul 07 2018

Valid Jul 07/1200 UTC thru Jul 11/0000 UTC

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

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

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

Overall Preference: Blend of 12Z GFS; 00Z ECMWF; 12Z NAM
                    (NAM only included through first 48 hours)
General Confidence: Average

Model agreement is generally very good over the first 48 hours or
so, with very little difference in the mass fields, and the
greatest uncertainty related to T.D. 3 off the East Coast.
Otherwise, a large ridge will dominate the weather pattern over
most of the CONUS. The WPC QPF forecast did prefer the 00Z ECMWF
and 12Z GFS more in the Upper Mississippi River Valley for the
position of the heavy rainfall axis, relative to the 00Z CMC and
00Z UKMET.

Beyond the first 48 hours, greater differences exist with the
trough that will be digging into the Northeast. The 00Z UKMET has
the trough axis (and upstream ridge axis) displaced further west
compared to the other models, and the 00Z CMC is much flatter with
the trough through the Mid Atlantic Region (extending the upper
level high further east than the other models). The 12Z NAM,
meanwhile, shows the the trough digging more than other models.
The preference, therefore is to trend toward a blend of the ECMWF
and GFS, which is close to the ECMWF and GEFS ensemble means.


...Tropical Depression Three off the East Coast...

Preference: Model consensus is closest to 15Z NHC Advisory
Confidence: See NHC products for more information

Model spread begins to increase after the first 24 hours of the
forecast, and no individual model is an exact analog for the NHC
forecast track. An average of available models -- 12Z NAM and GFS;
00Z ECMWF, CMC, UKMET -- is the closest approximation for the NHC
track at this time. Please see the latest NHC products for the
official forecast and an evaluation of forecast confidence.


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

Lamers