Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
147 PM EDT Fri Jun 15 2018

Valid Jun 15/1200 UTC thru Jun 19/0000 UTC

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

12Z Model evaluation of the NAM/GFS...with preliminary preferences
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...Overall model diagnostic analysis for the CONUS...

Preliminary preference: A blend of the 12Z GFS/00Z ECMWF, although
the 00Z UKMET is useful as well
Forecast confidence: Slightly above average outside of areas of
mesoscale focus
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...Primary features of interest between 15/1200Z - 19/0000Z...

1) Remnants of Tropical Depression Bud
2) Disturbance lifting out of the southwestern Gulf of Mexico
3) Mean upper low anchored over the Central Great Basin
4) Myriad of shortwaves rising out of the Four Corners into the
north-central U.S.
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...Discussion...

(1,2) On the large-scales, differences are minimal through at
least Day 2 given fairly well clustered forecast solutions.
Tropical Depression Bud weakens over the northern interior of
Mexico with remnant vorticity and moisture pushing into the Four
Corners and areas farther downstream. Remaining in the subtropics,
an area of disturbed weather currently given a 10% probability for
tropical cyclone development by NHC should lift toward the Texas
coast the next couple of days. The 12Z NAM/00Z CMC stand out as
outliers forming a low center so plan on sticking with a surface
trough at this point.

(3,4) Considering the eventual upper low semi-permanently set up
over the western U.S., decent synoptic-scale agreement is evident
through roughly early Sunday. Eventually the 12Z NAM becomes too
quick with the northern extent of the surface boundary across the
Upper Great Lakes. Additionally, the 00Z CMC begins to stand out
as an outlier aloft as it forces a rather significant trough into
the Northern High Plains by 18/1200Z. Otherwise all other issues
with the evolving pattern will be more on the mesoscale with
differences numerous throughout the period.


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

Rubin-Oster