Storm Prediction Center Mesoscale Discussion 586

   Mesoscale Discussion 0586
   NWS Storm Prediction Center Norman OK
   0225 PM CDT Mon Apr 28 2025

   Areas affected...central/southeast MN...western WI...northern IA

   Concerning...Severe potential...Tornado Watch likely 

   Valid 281925Z - 282130Z

   Probability of Watch Issuance...95 percent

   SUMMARY...Severe thunderstorm potential will increase through late
   afternoon. All severe hazards, including tornadoes (some strong),
   very large hail (to 3 inch diameter) and damaging gusts (to 70 mph)
   are possible.

   DISCUSSION...A line of convection along a surface front across
   southwest MN into northwest IA will continue to shift east/northeast
   this afternoon. Ahead of this convection, the downstream airmass
   across central/southeast MN, northern IA and western WI continues to
   moisten and destabilize. Surface dewpoints have increased into the
   low to mid 60s as far north as the Minneapolis metro area, with
   upper 50s to near 60 F to the north and east. Continued northward
   moisture transport on a 50+ kt low level jet should continue to aid
   in further destabilization over the next few hours as large-scale
   ascent overspreads the region. 

   Region VWP data from KMPX/KDMX/KARX already show impressive vertical
   shear favorable for supercells. Enlarged, curved low-level
   hodographs amid the strengthening low-level jet is aiding in 0-1 km
   SRH greater than 250 m2/s2. As weak MLCIN continues to erode,
   convection moving into this environment is likely to become better
   organized, with an increase in storm coverage expected into northern
   IA. Intense convection is expected to move across the MCD from late
   this afternoon into this evening, posing an all-hazards severe risk.
   A tornado watch will likely be needed in the next 1-2 hours.

   ..Leitman/Hart.. 04/28/2025

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

   ATTN...WFO...DVN...DLH...ARX...MPX...DMX...

   LAT...LON   42299364 42419255 42649166 42859095 43209086 44389096
               45279158 45589193 45799230 45909268 45879316 45779350
               45579402 45119422 44129443 42629478 42519477 42349412
               42299364 

   MOST PROBABLE PEAK TORNADO INTENSITY...140-170 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN