MESO Discussion MN/IA/WI 0569
From
Mike Powell@618:250/6 to
All on Mon Apr 27 14:01:04 2026
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
ACUS11 KWNS 271752
SWOMCD
SPC MCD 271752
WIZ000-IAZ000-MNZ000-272015-
Mesoscale Discussion 0569
NWS Storm Prediction Center Norman OK
1252 PM CDT Mon Apr 27 2026
Areas affected...southeast Minnesota...northeast Iowa...and
southwest Wisconsin
Concerning...Severe potential...Watch unlikely
Valid 271752Z - 272015Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated severe storms are possible this afternoon with
the primary hazard being hail up to 1.0-1.5" in diameter.
DISCUSSION...Early-afternoon water-vapor imagery indicates a
vigorous vorticity maximum over northern IA into southern MN,
lifting to northeast. At the surface, 17z analysis placed a low over south-central MN with a cold front trailing to the south-southwest,
and a trough/wind shift extending southeast into eastern IA.
Convection is in the process of deepening as of 17z along the cold
front in north-central IA amidst a marginally unstable air mass with
estimated MLCAPE of 250-500 J/kg, per objective analysis. Breaks in
the clouds ahead of the cold front will allow for further
destabilization this afternoon, especially given the height
falls/mid-level cooling overspreading the region from the
west/southwest. As such a few strong to potentially severe storms
are expected to develop along and ahead of the surface low and cold
front this afternoon with the primary hazard being hail up to
1.0-1.5" in diameter.
Veered low-level winds (evident in RAP forecast soundings) are
expected to limit a more robust tornado threat, at least along the
cold front. A potentially more favorable low-level wind profile
likely exists along/east of the surface wind shift preceding the
cold front. The most likely location for a brief spin up is along
and to the southeast of the surface low track where local maximum in
surface vorticity will coincide with 0-3-km CAPE of 100-125 J/kg.
..Mead/Guyer.. 04/27/2026
ATTN...WFO...MKX...DVN...ARX...MPX...DMX...
LAT...LON 43249360 44199277 44519158 44128998 42799001 42249125
42079218 42519343 43249360
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)