Mesoscale Discussion 0587
NWS Storm Prediction Center Norman OK
0328 PM CDT Mon Apr 28 2025
Areas affected...far southeast NE...southwest into central
IA...northwest MO...northeast KS
Concerning...Severe potential...Watch likely
Valid 282028Z - 282300Z
Probability of Watch Issuance...95 percent
SUMMARY...Widely scattered thunderstorms will pose a risk for a few
tornadoes (a couple strong), large to very large hail (up to 3 inch
diameter), and isolated damaging gusts through evening. A tornado
watch will likely be needed for portions of the discussion area from
central Iowa into northeast Kansas.
DISCUSSION...Deepening cumulus is noted along a dryline from eastern
NE/northwest IA southward into northeast KS. An 18z RAOB from OAX
indicated an EML around 700 mb, but only weak capping remained.
Additional heating into the low/mid 80s F amid mid/upper 60s F
dewpoints beneath steep midlevel lapse rates around 7.5-8.5 C/km
immediately downstream from the surface dryline is support strong
instability with MLCAPE greater than 2000 J/kg noted in latest SPC
Mesoanalysis and the 18z OAX RAOB. In addition to this this
favorable thermodynamic environment, vertical shear is very
favorable for supercell thunderstorms, as evident in enlarged,
looping low-level hodographs becoming somewhat elongated above 2-3
km.
Large-scale ascent will remain somewhat weaker with southward extent
into the MO Valley vicinity, and storm coverage is a bit uncertain,
especially with southward extent. Timing of convective initiation is
also uncertain, but seems most likely in the 22-00z time frame.
Regardless, any storms developing in this environment will likely
have robust updrafts and become intense, posing a risk for very
large hail, a few tornadoes and damaging gusts. A tornado watch will
likely be needed for portions of the MCD area in the next 1-2 hours.
..Leitman/Hart.. 04/28/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DMX...EAX...OAX...TOP...ICT...
LAT...LON 38269539 38139646 38329715 38529730 39859664 40239643
40809631 41419618 41989598 42139573 42249507 42249396
42229357 42119323 41839294 41459282 40929282 40489283
39839318 39159389 38269539
MOST PROBABLE PEAK TORNADO INTENSITY...120-150 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN
Category: Watches, Warnings, Advisories, & Hazards