Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
251 AM EDT Tue Jun 05 2018

Valid Jun 05/0000 UTC thru Jun 08/1200 UTC

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

00Z model evaluation including final preferences
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...Closed low/upper trough over southern Quebec sliding thru the
Northeast today...
...Associated surface low moving through southern Quebec and
redeveloping over SE New England today...
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Preference: General model blend
Confidence: Slightly above average

Trends over the past 24 hours have been convergent, with any
remaining differences small enough to be smoothed out by using a
general model blend. The 00Z CMC trended slower at 500 mb into the
western Atlantic and is now close enough to the remaining models
regarding the redeveloped surface low off of New England to be
included in the general model blend. Ensemble scatter low plots
show relatively tight clustering through Wednesday morning before
the low moves well offshore and is no longer a threat to the U.S.


...Lower MS valley shortwave advancing southeastward and stalling
in the NE Gulf thru Thurs...
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Preference: non 00Z CMC blend
Confidence: Slightly above average

The models are in good agreement with this feature until it
reaches the eastern Gulf of Mexico and Florida. The 00Z CMC IS
FASTER to move the trough axis eastward, whereas the consensus in
the deterministic and ensemble guidance is back toward the west.
The 00Z ECMWF trended slower from its previous 12Z cycle and can
now be used as part of the preference. Trends in the GFS have been
slower and so given the greater support for a slower progression
to the east, a non 00Z CMC blend is recommended with this system.
Outside of the 00Z CMC, the 00Z NAM is displaced a bit south of
the 00Z GFS/ECMWF/UKMET but is still reasonable given the ensemble
spread.


...Mid-level shortwave moving across southern Canada through
Thursday with accompanying surface low/front...
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Preference: General model blend
Confidence: Slightly above average

The models show similarly with this system.


...Large closed low off of the British Columbia coast through the
end of the week...
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Preference: General model blend
Confidence: Slightly above average

The models show similarly with this system with only small scale
timing differences through Friday morning.


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

Otto