Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
132 AM EST Mon Nov 11 2019
Valid Nov 11/0000 UTC thru Nov 14/1200 UTC
..See NOUS42 KWNO (ADMNFD) for the status of the upper air
ingest...
...00Z Model Evaluation with Final Preferences and Confidence...
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...Amplifying mid-level trough into the north-central U.S./Great
Lakes today/tonight...
...Surface low in the vicinity of New England Tuesday morning...
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Preference: General model blend
Confidence: Above Average
The 00Z UKMET adjusted slower for Tuesday with its mid-level
trough progression, toward the remaining model consensus compared
to its 12Z cycle. Therefore, given the good agreement with all of
the available models, a general model blend is preferred.
...Cold front nearing the Pacific Northwest on Tuesday and
accompanying shortwave into the Great Plains on Wednesday...
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Preference: General model blend
Confidence: Slightly above average
The latest deterministic models are in fairly good agreement with
a cold front into the Pacific Northwest and the corresponding
shortwave downstream into the Great Plains on Wednesday. While
some minor timing differences regarding the mid-level shortwave
show up by Thursday morning with the 00Z GFS fastest, the
differences are small enough though that time to support a general
model blend.
...Closed low currently over the Baja Peninsula...
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Preference: non 00Z NAM blend
Confidence: Average
While a subtle trend to be faster has been noted in the ensembles
Thursday morning, the 12Z UKMET remains faster than a majority of
the latest models. The 00Z UKMET slowed down enough to be included
as part of a blend while the 00Z ECMWF sped up slightly from its
12Z cycle. The 00Z NAM was slightly slower with the 00Z GFS by
Thursday morning while the CMC remained consistent. The 00Z NAM is
the only model to stand out enough to exclude it from the
preference.
...Weakening shortwave trough approaching California mid-week...
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Preference: General model blend
Confidence: Slightly below average
Timing differences with this shortwave are prevalent in the
ensemble members. Trends from the 00Z ECMWF/UKMET/CMC were toward
the middle of the ensemble spread and while the 00Z NAM/GFS were
toward the quicker side of the guidance, the faster trends in some
of the non NCEP guidance supports a general model blend at this
time. However, ensemble spaghetti heights show enough spread to
lower confidence below average for now.
Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml
Otto