MD 0819 CONCERNING SEVERE THUNDERSTORM WATCH 255… FOR SOUTHEASTERN NORTH DAKOTA AND NORTHEASTERN SOUTH DAKOTA
Mesoscale Discussion 0819
NWS Storm Prediction Center Norman OK
0807 PM CDT Fri May 17 2024
Areas affected…southeastern North Dakota and northeastern South
Dakota
Concerning…Severe Thunderstorm Watch 255…
Valid 180107Z – 180300Z
The severe weather threat for Severe Thunderstorm Watch 255
continues.
SUMMARY…Peak surface gusts associated with ongoing thunderstorms
have generally subsided, but could still increase once again across
parts of northeastern South Dakota and southeastern North Dakota
through 9-11 PM CDT.
DISCUSSION…Based on cooling cloud tops, radar and lightning data,
convection has undergone recent intensification in a cluster
centered across south central North Dakota, and now shifting east of
the Missouri River. This appears near the exit region of a
seasonably strong high-level jet streak nosing into the northern
high plains, which may help maintain convection as it spreads toward
the Red River Valley this evening.
Although probably unaccompanied by appreciable low-level moistening,
the Rapid Refresh indicates considerable strengthening of
south-southwesterly flow around 850 mb across central Nebraska
toward the Watertown SD vicinity through 02-04Z. Forcing on the
nose of this low-level jet may augment the upper support for
convection, in the presence of limited instability, and downward
mixing of this momentum could also support another uptick in
potential for severe surface gusts.
..Kerr.. 05/18/2024
…Please see www.spc.noaa.gov for graphic product…
ATTN…WFO…FGF…ABR…BIS…
LAT…LON 45530047 46269974 46649874 47179771 46689651 45799689
45219839 45149975 45530047
