Storm Prediction Center Mesoscale Discussion 216

   Mesoscale Discussion 0216
   NWS Storm Prediction Center Norman OK
   1140 AM CDT Wed Mar 11 2026

   Areas affected...portions of central/northern Maine

   Concerning...Winter mixed precipitation 

   Valid 111640Z - 112245Z

   SUMMARY...Precipitation will expand across portions of
   central/northern Maine through the afternoon/evening today with an
   accompanying increase in rates ahead of an approaching upper-level
   trough. Mixed precipitation is likely, with a gradual transition
   from snow/sleet to freezing rain expected through this evening.

   DISCUSSION...A surface cyclone is forecast to progress northeastward
   from Lower Michigan into southeastern Canada today, with an
   attendant warm front lifting northward across southern New England.
   Increasing isentropic ascent to the north of this frontal boundary
   coupled with favorable upper-level jet dynamics and a low-level
   frontogenetic zone are expected to support an increase in
   precipitation rates through this afternoon. Per the 12Z CAR
   sounding, atmospheric profiles are below freezing across much of
   northern Maine, but RAP forecast soundings indicate that a 850-700
   mb warm nose is beginning to build across central Maine. With
   surface temperatures ranging from the low-20s to low-30s F across
   the region, this is supporting snow/sleet as the initial
   precipitation types. With strong 850 mb warm air advection beginning
   to spread northward, the warm nose will gradually build throughout
   the afternoon, leading to a northward expansion of sleet and an
   eventual transition to freezing rain for much of central/northern
   Maine. The best chances for freezing rain rates to exceed 0.06
   inches per 3 hours through the afternoon is expected to span from
   the northern Kennebec Valley into the Central Highlands.

   A further increase in winter precipitation rates is then anticipated
   this evening into tonight as increasing DCVA downstream of an
   upper-level shortwave trough overspreads the region amidst the
   continuing strong, low-level warm air advection regime.

   ..Chalmers.. 03/11/2026

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

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

   LAT...LON   47526844 47386796 47106766 46626752 46456748 46116741
               45856739 45586753 45366792 45176849 45076909 45006989
               45057034 45187066 45447082 45657081 46127051 46767011
               47246968 47436943 47576909 47526844