Storm Prediction Center Mesoscale Discussion 2252

   Mesoscale Discussion 2252
   NWS Storm Prediction Center Norman OK
   0859 PM CST Sun Dec 08 2024

   Areas affected...Eastern Montana and far western North Dakota

   Concerning...Blizzard 

   Valid 090259Z - 090900Z

   SUMMARY...Sporadic blizzard conditions are likely through the
   overnight hours across eastern Montana and into far western North
   Dakota. Conditions are expected to deteriorate steadily between
   06-12 UTC as light to moderate snow fall rates coincide with 30-35
   mph winds.

   DISCUSSION...Temperatures across eastern MT have been steadily
   falling to below freezing as a cold front begins to push south into
   the northern Plains. This has been promoting a change over from a
   wintry mix to predominantly snow, which is expected to gradually
   spread southeast through early Monday morning as a surface low
   translates east along the international border. Sustained gradient
   winds between 30-35 mph are being observed with gusts upwards of
   40-45 mph. Blowing snow model output suggests that with light to
   moderate snow fall rates (0.25-0.5 in/hour) and temperatures in the
   low 30s, these sustained winds will result in sporadic/transient
   blizzard conditions with more significant/widespread visibility
   reductions likely where gusts exceed 40 mph. Early indications of
   this trend have already been noted across northeast MT where
   periodic visibility reductions down to 1/2 mile have been coincident
   with gusts over 40 mph. Such conditions should become more common
   across eastern MT/far western ND as the surface freezing line pushes
   south and supports snow as the primary precipitation type. Recent
   HRRR solutions suggest sporadic blizzard conditions will begin to
   impact the I-94 corridor as early as 05-06 UTC.

   ..Moore.. 12/09/2024

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

   ATTN...WFO...BIS...BYZ...GGW...

   LAT...LON   48760638 48770564 48700492 48540444 47410350 46950331
               46500343 46100377 45860421 45840482 45930550 46150620
               46550671 46950713 47420737 47950743 48230730 48590696
               48760638