Mesoscale Discussion 1664
NWS Storm Prediction Center Norman OK
0410 AM CDT Fri Sep 22 2017
Areas affected...Parts of central into northeastern Minnesota
Concerning...Severe potential...Watch unlikely
Valid 220910Z - 221145Z
Probability of Watch Issuance...20 percent
SUMMARY...Strong storms with gusty winds or marginally severe hail
are expected to persist across parts of central Minnesota into
northwest Wisconsin this morning, but the severe threat appears too
localized for a watch.
DISCUSSION...Scattered storms continue to develop over the area in a
region of theta-e advection associated with a 40-50 kt southwesterly
low-level jet and warm front. The air mass feeding into these storms
is very moist and unstable, but shear in the cloud-bearing layer is
very marginal for a sustained severe threat.
Though most cells have tended to be pulse in nature, one larger
cluster over central MN may be able to produce some cold pool of
consequence if it continues to grow in size. The low-level jet will
tend to veer with time, shunting the lift from warm advection
farther northeast. Any additional cells may contain a marginal hail
threat for a short period of time, with wind threat conditional on
clusters maintaining themselves long enough to produce a cold
pool/outflow.
..Jewell/Grams.. 09/22/2017
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DLH...MPX...FGF...
LAT...LON 45979569 46259599 46669536 47439348 47459261 47249179
46899148 46449130 46079167 45959279 45979569
Read morefrom SPC Forecast Products http://ift.tt/14zBs6B
No comments:
Post a Comment