Mesoscale Discussion 1746
   NWS Storm Prediction Center Norman OK
   1223 PM CDT Tue Oct 20 2020

   Areas affected...Central MN

   Concerning...Heavy snow 

   Valid 201723Z - 202030Z

   SUMMARY...Periods of snow, occasionally heavy, will affect portions
   of central MN through the afternoon.

   DISCUSSION...Latest IR satellite and radar imagery show a mid-level
   vorticity max over central SD.  A developing deformation zone on the
   north side of the impulse, along with a zone of enhanced low-level
   warm advection extending east-southeastward across south-central MN
   will help to raise precipitation rates through the next few hours. 
   A few lightning strikes have also been recently noted in northeast
   SD, suggesting further augmentation of precipitation.  Near surface
   temperatures are marginal for accumulating snow, but relatively high
   precipitation rates and a deep isothermal layer will result in at
   least mesoscale bands of heavy snowfall rates approaching 1"/hr
   across the discussion area.  

   Rapid mid-level drying and the back edge of important precipitation
   is moving eastward at over 30 knots across SD, and will begin to
   weaken snowfall rates from west-to-east over the area by
   mid-afternoon.

   ..Hart.. 10/20/2020

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

   ATTN...WFO...DLH...MPX...FGF...ABR...

   LAT...LON   45809626 46149337 45539269 44649284 44389429 44579522
               45039644 45809626