Mesoscale Discussion 2080
   NWS Storm Prediction Center Norman OK
   1141 AM CST Sat Dec 31 2022

   Areas affected...the higher terrain of the Sierra in northern
   California

   Concerning...Heavy snow 

   Valid 311741Z - 312345Z

   SUMMARY...Heavy snow is expected to increase in coverage across the
   higher terrain of the Sierra in northern California through the
   afternoon into early evening.

   DISCUSSION...A mid-level trough and accompanying stream of deep
   moisture continues to impinge on the higher terrain of the Sierra in
   northern CA. Strong deep-layer ascent along the windward side of the
   Sierra should lift the deep moisture to a saturated dendritic growth
   zone, favoring heavy snow production. The depth of the rich
   moisture, the presence of weak buoyancy, and combined orographic and
   dynamic lift of moist and buoyant air may foster snowfall rates up
   to the 3-5 inch/hr range, at least on a localized basis and
   particularly above 6000 ft elevations. Latest high-resolution
   guidance consensus suggests that the heavier snowfall rates should
   begin sometime between 18-20Z and become more widespread in the
   higher elevations in the 21-01Z time frame.

   ..Squitieri.. 12/31/2022

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

   ATTN...WFO...VEF...REV...HNX...STO...

   LAT...LON   39692049 38941999 38391942 38141925 37741893 37481857
               37191831 36961835 36991866 37421925 37921972 38642031
               39062057 39332062 39682064 39692049