Mesoscale Discussion 1229
NWS Storm Prediction Center Norman OK
0333 PM CDT Tue Jul 04 2017
Areas affected...eastern North Dakota...northern Minnesota
Concerning...Severe potential...Watch likely
Valid 042033Z - 042300Z
Probability of Watch Issuance...80 percent
SUMMARY...Thunderstorms will begin forming after 21Z across
northeast North Dakota into northwest Minnesota, becoming most
numerous after 00Z. At least isolated large hail and severe wind
gusts are expected. A watch is likely, perhaps in the next hour.
DISCUSSION...Strong heating continues ahead of a cold front which
extends from southern Manitoba into western SD. A plume of better
low-level moisture continues to spread northward with axis across
western MN and toward the Red River. Here, dewpoints are in the mid
to upper 60s with precipitable water values in excess of 1.30".
This, combined with steep lapse rates aloft are producing MUCAPE of
The cold front will drift southward with time, as a weak low
amplitude shortwave trough passes to the north. Several more hours
of heating along with lift along the front will lead to scattered
storms, with large hail and damaging wind expected. Winds veer with
height, but are relatively weak, thus brief supercells are possible
but an eventual MCS is expected.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 48819461 48749424 48689387 48589363 48679304 48629281
48509250 48379198 48239178 46729322 46389386 46289517
46279718 46469839 46949882 49049780 49049522 49469518
49419485 49159470 48819461