Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
136 AM EST Thu Nov 28 2019
Valid Nov 28/0000 UTC thru Dec 01/1200 UTC
...See NOUS42 KWNO (ADMNFD) for the status of the upper air
ingest...
00Z Model Evaluation with Preferences and Forecast Confidence
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...Strong upper low over the Northeast...
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Preference: General model blend
Confidence: Above average
Model spread is minimal with the strong upper low crossing into
the Northeast. This system will quickly move offshore by late
Thursday. A general model blend will be preferred with this system.
...Deep closed low crossing the Intermountain West/Plains...
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Preference: Blend of the 00Z NAM and 00Z ECMWF
Confidence: Slightly above average
Some of the biggest model differences relate to the deep layered
closed low currently near the CA/OR border. The height falls with
this system will translate east across the Intermountain West
Friday, and then reorganize and deepen across the High Plains and
Midwest on Saturday along with a notably strong surface low. The
00Z GFS by 36 hours edges stronger than any other piece of
guidance while traversing the West, and becomes a deep outlier by
Saturday across the Plains. Meanwhile, the 00Z UKMET is overall
the weakest solution through the period. The 00Z CMC is actually
relatively weak as well compared to the multi-model consensus and
the ensemble suites per the GEFS and ECENS. Overall, as the system
crosses the Plains and aims for the Midwest, the 00Z NAM and 00Z
ECMWF appear to have some of the better clustering and support
from the GEFS mean and ECENS mean. And so a blend of these two
solutions will be preferred with this specific closed low.
...Upper low approaching the West Coast by Sunday...
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Preference: Blend of the 00Z GFS and 00Z ECMWF
Confidence: Average
By the end of the period, a new closed low will be evolving
offshore of the West Coast along with low pressure at the surface.
The 00Z CMC and 00Z UKMET both appear to be a tad too weak with
this system. The best model clustering with this system tends to
reside with the 00Z GFS and 00Z ECMWF, and so a blend of these
solutions will be preferred which is also reasonably well
supported by the latest GEFS mean and ECENS mean.
Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml
Orrison