Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
114 AM EDT Sat Jun 06 2020
Valid Jun 06/0000 UTC thru Jun 09/1200 UTC
...See NOUS42 KWNO (ADMSDM) for the status of the upper air
ingest...
00Z Initial Model Evaluation Including Preferences and Confidence
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...Amplifying wave shifting east across the Northeast tonight...
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Preference: Non-CMC General Model Blend
Confidence: Slightly above average
A positively tilted trough extending from northern Quebec to
central Ontario amplifies as it pushes east across the Northeast
and Mid-Atlantic tonight. The 12Z CMC is the deepest solution and
is the only outlier.
...Low over southern California crosses the Great Basin today, the
Wyoming Rockies this evening, and the northern Plains tonight.
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Preference: General Model Blend
Confidence: Slightly above average
The 00Z GFS remains a bit more amplified as the trough lifts over
the northern Plains near the MT/ND border tonight, but not enough
to be ruled out of the excellent agreeing consensus among global
deterministic guidance.
...Closed low drifting south off British Columbia then shifting
into Washington/Oregon Saturday tonight and a northern trough
drifting east across the northern Rockies Sunday through Monday...
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Preference: General Model Blend
Confidence: Slightly above average
Well defined symmetric closed low off BC is well forecast through
the short-term as it makes landfall into the Pacific Northwest
through the weekend. Uncertainty arises as the central core
enhanced by the Pacific jet rounds the broadening base into the
Snake River Valley/Great Basin and begins to interact with the
exiting shortwave lifting through the northern Plains. Still, most
of the uncertainty comes with differences in timing within the
guidance suite and therefore the magnitude of amplification with
the precursory wave moving into SW Canada. The GFS and NAM remain
the most aggressive and swing the jet through WY into MT stronger
and faster. The 12Z UKMET is the slowest solution, but the
overall minor differences make a general model blend preferred.
...Cristobal...
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Preference: 03Z NHC advisory
Confidence: Refer to NHC products
The official track for T.S. Cristobal is on the faster side of
guidance, closest to the 12Z CMC for timing into the central Gulf
coast late Sunday and into the Mid-South by late Monday. There is
tight clustering of the low position with the 12Z UKMET the
deepest in terms of central pressure by a few millibars. The 00Z
GFS slowed in its Day 1 timing across the central Gulf. The 00Z
NAM remains the westernmost of the global guidance for the remnant
inland track on Day 3.
Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml
Jackson