Mesoscale Discussion 2187
   NWS Storm Prediction Center Norman OK
   0500 AM CST Tue Dec 03 2019

   Areas affected...Portions of Maine

   Concerning...Heavy snow 

   Valid 031100Z - 031700Z

   SUMMARY...Heavy snow will develop this morning across coastal Maine
   and shift slowly westward across the state over the next several
   hours. Snowfall rates of 1-2 inches per hour will be likely, with 3
   inches per hour possible.

   DISCUSSION...A powerful mid/upper-level low east of Cape Cod MA this
   morning will develop northward into the Gulf of Maine, as a related
   surface low likewise deepens over the same area. A consolidating
   deformation band already evident on recent radar imagery just off
   the coast is being aided by robust low-level warm
   advection/frontogenesis and upper-level divergence as both the upper
   and surface low strengthen. This band is forecast to shift slowly
   westward this morning from parts of coastal into interior ME as the
   overall cyclone moves north-northeastward. A residual warm nose
   centered around 800 mb may support a mix of sleet with snow
   initially along/near the coast. However, a quick changeover to all
   snow appears likely after the first hour or two of substantial
   precipitation as temperatures in the 850-700 mb layer cool slightly.
   Saturation of the column will extend well above the dendritic growth
   zone, and the strong ascent associated with the mid-latitude cyclone
   will support enhanced snowfall rates of 1-2 inches per hour within
   the deformation band. Locally higher rates up to 3 inches per hour
   are not out of the question based on recent short-term guidance.

   ..Gleason.. 12/03/2019

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

   ATTN...WFO...CAR...GYX...

   LAT...LON   43437026 43677002 43736971 43866922 43976879 44216842
               44716762 45186713 45796763 46926764 46986796 46806847
               46166923 45166983 44547016 43837035 43437026