Mesoscale Discussion 1685
   NWS Storm Prediction Center Norman OK
   0334 AM CDT Tue Sep 08 2020

   Areas affected...Southern WY...Far Southwest SD...Far Northwest NE
   Panhandle

   Concerning...Heavy snow 

   Valid 080834Z - 081230Z

   SUMMARY...Snowfall rates around 1"/hr are possible across lower
   elevations over the next few hours. Rates of 2-3"/hr are possible
   over higher elevations.

   DISCUSSION...A strong shortwave trough continues to dig
   south-southeastward through the eastern Great Basin toward the
   central Rockies. Evolution of this shortwave is contributing to
   strong forcing for ascent near and behind a vigorous cold front
   pushing through the central Plains/central High Plains. Banded
   precipitation has resulted from the central High Plains into the
   central Plains over the past few hours, with moderate to heavy snow
   occasionally reported in those areas where profiles are cold enough.

   Based on recent observations and RAP forecast soundings, the area
   from southwest WY northeastward into far southwest SD/far northwest
   NE Panhandle is expected to be cold enough for snow over the next
   few hours. Snowfall rates in these areas could approach 1"/hr across
   the lower elevations and 2"-3"/hr over the higher terrain. This is
   evidenced by recent storm reports indicating 6" to 8" of snow has
   already fallen in Lawrence County SD (in the Black Hills).
   Additionally, blizzard conditions were recently reported at RKS and
   EMM in southwest WY.

   ..Mosier.. 09/08/2020

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

   ATTN...WFO...UNR...CYS...RIW...SLC...

   LAT...LON   41971066 43010852 43560522 44310373 43890278 42180430
               41190743 41031045 41971066