Mesoscale Discussion 1114
NWS Storm Prediction Center Norman OK
0725 PM CDT Wed Jun 21 2017
Areas affected...southeast North Dakota...western Minnesota...and
northeast South Dakota
Concerning...Severe Thunderstorm Watch 361...
Valid 220025Z - 220230Z
The severe weather threat for Severe Thunderstorm Watch 361
SUMMARY...Scattered strong/locally severe thunderstorms continue
across WW 361, where severe risk continues.
DISCUSSION...Latest radar loop shows thunderstorms moving generally
eastward across areas in/near WW 361, with a few severe/supercell
storms evident based on radar characteristics. Storms across
northwest Minnesota continue to gradually weaken, consistent with
the fact that the axis of greatest instability remains within a
north-south axis near the North Dakota/Minnesota border. As storms
continue to encounter more stable air into north central Minnesota,
expect the weakening trend to continue.
Farther south, a supercell storm roughly 30 miles northwest of
Chandler, MN (AXN) is moving east-southeast, roughly along the
northern edge of a northwest-to-southeast instability gradient
paralleling a surface warm front extending from southeast Minnesota
across Iowa. While this storm will likely shift gradually
east-southeastward out of the watch, and continue to pose a severe
risk including potential for an isolated tornado, threat is not
expected at this time to become areally substantial enough
east/southeast of WW 361 to warrant new WW issuance.
Finally, storms remain weaker across northeast South Dakota, farther
from the influence of the upper system crossing southern portions of
the Canadian Prairie at this time. Still, an isolated/briefly
severe storm may affect southwest portions of the WW over the next
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 44699899 45339862 46669689 47549623 48309632 48429425
47159417 45819448 44619418 44239515 44819723 44699899