Mesoscale Discussion 1725
   NWS Storm Prediction Center Norman OK
   0409 AM CDT Wed Sep 30 2020

   Areas affected...Southeast New England

   Concerning...Severe potential...Watch unlikely 

   Valid 300909Z - 301045Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Isolated damaging gusts will be possible this morning,
   prior to frontal passage.

   DISCUSSION...A narrow band of shallow frontal convection (without
   lightning) is moving eastward into western MA/CT and Long Island. 
   The convection is focused along a surface cold front that will move
   eastward across southern New England this morning, as a surface low
   near the NY/MA border moves north-northeastward and deepens in
   advance of an ejecting shortwave trough over VA/MD/PA.  The primary
   limiting factor for a severe-storm threat will be poor lapse rates
   aloft and near the surface, leading to very weak buoyancy despite
   boundary-layer dewpoints of 68-70 F.  Still, the near moist neutral
   profiles, strong forcing for ascent along the front, and 60-70 kt
   flow to within a km of the ground will support some potential for
   downward momentum transfer in the stronger convective elements.  The
   threat for isolated damaging winds will persist until frontal
   passage occurs across eastern MA/Cape Cod around 14z.

   ..Thompson.. 09/30/2020

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

   ATTN...WFO...GYX...BOX...OKX...ALY...

   LAT...LON   40677307 41567317 42457295 43167248 43277170 43027075
               42197050 41577073 41147115 40677307