Mesoscale Discussion 0042
   NWS Storm Prediction Center Norman OK
   0310 PM CST Sat Jan 11 2020

   Areas affected...Central/eastern MO...Central/northern IL

   Concerning...Heavy snow 

   Valid 112110Z - 120115Z

   SUMMARY...Mixed precipitation should transition to snow later this
   afternoon into this evening. Snowfall rates of 1 inch/hour will be
   possible the strongest bands.

   DISCUSSION...At 21Z, WV imagery depicts a strong negatively-tilted
   mid/upper trough ejecting northeastward toward the mid-MS Valley,
   with a midlevel dry slot spreading into portions of southeast MO and
   southern IL. Moderate to occasionally heavy snow has been reported
   over the last few hours across southeast KS into western MO in
   association with this system. As the system spreads northeastward,
   ongoing snow bands will spread into northeast MO and western IL,
   while the mixed precipitation shield further to the south should
   transition to snow as continued deep-layer ascent and low-level cold
   advection cool the column. While the duration of snow at any
   location is not expected to be particularly long, heavy snow rates
   of 1 inch/hour will be possible within the strongest bands. 

   Heavier snow rates may spread into northern portions of the St.
   Louis metro area by 22-23Z, and develop northeastward toward the
   Chicagoland area by 00Z.

   ..Dean.. 01/11/2020

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

   ATTN...WFO...LOT...ILX...LSX...DVN...SGF...EAX...

   LAT...LON   39059261 40369123 41538973 42338832 42258769 41998765
               41188758 40068877 39598959 38769041 37839127 37319235
               38229283 39059261