Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
102 AM EDT Sun Jun 07 2020
Valid Jun 07/0000 UTC thru Jun 10/1200 UTC
...See NOUS42 KWNO (ADMSDM) for the status of the upper air
ingest...
00Z Model Evaluation Including Initial Preferences and Confidence
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...Closed low over the Pacific Northwest swinging across the
northern Rockies late today...
...Associated upper trough moving from the Great Basin to the
Great Plains tonight through Tuesday...
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Preference: Non-GFS/NAM blend
Confidence: Average
While the general pattern of the upper low swinging east from the
Pacific Northwest today lifting across northeast Montana into
Saskatchewan on Monday there are strength issues. The 00Z NAM and
GFS keep a closed low across the Rockies into MT and the GFS/18Z
GEFS further strengthen the low over Saskatchewan on Monday while
non-NCEP guidance opens the low over the ID/MT Rockies tonight and
keeps a trough axis over the northern Plains through Monday night
before absorbing Cristobal remnants. This stronger low/trough over
the northern Plains in the NAM/GFS pushes the trough farther east
which makes for convergence/predecessor rain from Cristobal
farther east over the north-central Plains on Day 2 than non-NCEP
guidance. Particularly with the GFS, the eastern favoring brings
Cristobal remnants farther north quicker. Will have to see what
the non-NCEP guidance does with 00Z runs to have a full-handle and
the final preference may change.
...Cristobal...
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Preference: 03Z NHC advisory
Confidence: Refer to NHC products
The 03Z NHC track is on the faster side of the global sfc low
center progs with only the 00Z GFS outpacing it through the Day 3
time frame. As noted above the GFS is the fastest solution with
Cristobal, likely due to a stronger low over the Canadian Prairies
Monday shunting the trough farther east with an earlier
interaction with Cristobal than the rest of the guidance. The 12Z
UKMET takes the slowest turn across the mid Mississippi valley
toward the Great Lakes. The 12Z ECMWF has shifted east and shows
good agreement with other non-NCEP guidance, just a little slower
than the NHC track.
Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml
500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml
Jackson