339
ACUS11 KWNS 241017
SWOMCD
SPC MCD 241017
ILZ000-IAZ000-MOZ000-241215-

Mesoscale Discussion 0926
NWS Storm Prediction Center Norman OK
0517 AM CDT Fri May 24 2024

Areas affected...Iowa/northern Missouri

Concerning...Severe Thunderstorm Watch 299...300...

Valid 241017Z - 241215Z

The severe weather threat for Severe Thunderstorm Watch 299, 300
continues.

SUMMARY...Severe-weather risk -- including damaging winds, hail, and
a tornado or two -- continues across WW 300.  Greatest risk is
evident across central and southern Iowa -- near and south of the
surface warm front.

DISCUSSION...Latest radar loop shows the well-established/organized
convective line moving eastward across Iowa, and now merging (in
central IA) with cellular convection which had developed east of the
main line.  A particularly interesting interaction has recently
occurred south/southeast of Des Moines, where rapid upscale
supercellular evolution was observed within a bowing segment of the
line, subsequent to merger of the bow with one of these more
isolated convective elements.  Radar data from KDMX appeared to
confirm a brief tornado.

Elsewhere, damaging winds, and occasional/brief tornadic spin-ups
remain possible.  Risk appears to wane with northward extent toward
the Minnesota border, especially into northeastern Iowa where a much
cooler/more stable airmass exists to the northeast of the
central/southeastern Iowa warm front.  South of that front however,
severe weather remains likely as convection continues advancing
eastward over the next couple of hours.

..Goss.. 05/24/2024

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...LSX...DVN...ARX...DMX...EAX...

LAT...LON   39709477 40339493 41149357 42079404 43019429 42999326
            42899216 42459093 41009093 40039148 39709477