Mesoscale Discussion 2109
   NWS Storm Prediction Center Norman OK
   0856 PM CDT Wed Oct 23 2019

   Areas affected...Portions of southeast Colorado

   Concerning...Heavy snow 

   Valid 240156Z - 240800Z

   SUMMARY...Heavy snow will be mainly confined to the higher terrain
   of the rockies. Some heavier rates may occur across southern
   portions of the Colorado Front Range, mainly across the Palmer
   Divide and the higher terrain of Las Animas and Huerfano Counties,
   with a few instances of 1 inch/hr snowfall rates possible. Heaviest
   snowfall rates will most likely be observed in the 04-08Z time
   frame.

   DISCUSSION...A cold front, currently located across far southeast
   Colorado, will continue to surge south throughout the evening in
   conjunction with a positively tilted mid-level shortwave trough.
   While temperatures are at or above freezing across much of southeast
   Colorado in the low-levels, sfc-700 mb layer cold air advection (per
   00Z Mesoanalysis) will promote temperatures cooling to at/below
   freezing, with saturation also occurring throughout the column. This
   cooling/saturating of the lower troposphere will support the
   development of a deep (up to 1km) dendritic growth layer,
   accompanied by strong lifting (925-700 mb frontogenesis) associated
   with an eastward, upslope component of low-level flow. 

   While much of the heavy snow will be confined to the higher terrain
   of the Rocky Mountains, up to 1 inch/hr snowfall rates appear
   possible across southern parts of the Colorado Front Range. The most
   likely places to experience 1 inch/hr rates will be along the
   northern slopes of the Palmer Divide and higher terrain of Las
   Animas/Huerfano Counties, where orographic lift may locally enhance
   low-level ascent.  The best time for 1+ inch/hr rates will be
   between 04-08Z (as supported by both 12Z HREF and several of the
   latest HRRR runs), when an easterly component of low-level flow will
   be most dominant.

   ..Squitieri/Darrow.. 10/24/2019

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

   ATTN...WFO...GLD...PUB...BOU...

   LAT...LON   37010352 37040413 37350464 37590491 37990497 38270512
               38480505 38670491 39330490 39460419 39140326 38460308
               37540278 37110275 37010352