Storm Prediction Center Mesoscale Discussion 1409

   Mesoscale Discussion 1409
   NWS Storm Prediction Center Norman OK
   0552 PM CDT Sun Jun 22 2025

   Areas affected...northern Minnesota

   Concerning...Tornado Watch 451...

   Valid 222252Z - 230045Z

   The severe weather threat for Tornado Watch 451 continues.

   SUMMARY...The tornado threat is likely increasing across northern
   Minnesota as thunderstorms develop within a favorable environment.

   DISCUSSION...GOES visible and IR imagery show steady vertical growth
   of convection across north-central MN along and north of a warm
   front and to the west ahead of a cold front. Based on recent RAP
   forecast soundings, areas that have temperatures in the mid 70s or
   higher will likely support surface-based convection within the warm
   frontal zone where backed low-level winds are yielding effective SRH
   on the order of 200-250 m2/s2. Increasing low to mid-level ascent
   associated with the approach of an upstream perturbation and within
   the warm advection regime should promote continued storm maturation
   and coverage over the next couple of hours. Given that the number of
   candidate storms appears to be increasing within this narrow, but
   very favorable environment (best characterized by STP values between
   3-5), the potential for tornadoes - including strong tornadoes - may
   increase in the coming hours if one or more mature supercells can
   maintain sufficient residence time within this corridor.

   ..Moore.. 06/22/2025

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

   ATTN...WFO...DLH...FGF...

   LAT...LON   47849331 47569477 47569552 47569605 47659636 47939650
               48449623 48889594 48949564 48869514 48549457 48479411
               48469355 48489322 48379297 48099294 47909312 47849331 

   MOST PROBABLE PEAK TORNADO INTENSITY...100-130 MPH
   MOST PROBABLE PEAK WIND GUST...65-80 MPH
   MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN