Mesoscale Discussion 0869
NWS Storm Prediction Center Norman OK
1027 AM CDT Tue May 21 2024
Areas affected...Eastern NE...Western IA...Far Southeast SD
Concerning...Severe potential...Watch likely
Valid 211527Z - 211730Z
Probability of Watch Issuance...80 percent
SUMMARY...Fast-moving supercells capable of all severe hazards will
be possible, including large to very large hail, strong gusts up to
70 mph, and tornadoes. A Tornado Watch will likely be needed for
portions of the area with in the next hour or two.
DISCUSSION...Recent surface analysis places the primary surface low
over north-central KS (just southwest of CNK), with a warm front
extending northeastward into southeast NE and then more
east-northeastward across southern IA. A cold front also extends
from this low southwestward through central KS and the eastern OK
Panhandle. There is a secondary surface low farther north near the
IA/SD/MN border intersection, with weak surface troughing connecting
these two lows.
Given the position of the surface features, the recent thunderstorm
activity along the central NE/KS border is likely elevated,
initiated by strong ascent attendant to the approaching shortwave
trough. However, as the primary surface low moves quickly
northeastward, and the warm front correspondingly moves northward,
the airmass across eastern NE and western IA (particularly
east-central/southeast NE and west-central/southwest IA) is expected
to become increasingly supportive of surface-based storms. Within
the warm sector, fast-moving supercells capable of all severe
hazards will be possible, including large to very large hail, strong
gusts up to 70 mph, and tornadoes. Large hail and strong gusts will
be possible with the elevated storms as well. Given this severe
potential, a Tornado Watch will likely be needed for portions of the
area with in the next hour or two.
..Mosier/Guyer.. 05/21/2024
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DMX...EAX...FSD...OAX...
LAT...LON 41339704 42939678 42989574 42349509 40339546 40159723
41339704