Mesoscale Discussion 1947
   NWS Storm Prediction Center Norman OK
   0309 PM CST Sat Nov 13 2021

   Areas affected...Parts of eastern Massachusetts

   Concerning...Severe potential...Watch possible 

   Valid 132109Z - 132315Z

   Probability of Watch Issuance...40 percent

   SUMMARY...A line of thunderstorms may be maintained, and overspread
   much of eastern Massachusetts during the 5-7 PM EST time frame. 
   This may be accompanied by a risk for localized, potentially
   damaging, wind gusts.  It is not yet clear that another severe
   weather watch will be needed, but trends will continue to be
   monitored, and it is possible that Severe Thunderstorm Watch 549
   could be locally extended in area  across parts of this region

   DISCUSSION...As the deepening surface low tracks across
   southern/southeastern New England into early evening,
   clockwise-curved low-level hodographs appear likely to continue to
   enlarge within its warm sector.  However, latest Rapid Refresh
   forecast soundings indicate that southeasterly near surface flow off
   the Atlantic will maintain relatively low surface dew points in the
   lower/mid 40s F across much of eastern Massachusetts.  They do
   indicate that a weak to modest elevated moisture return may
   contribute to sufficient CAPE to maintain the approaching line of
   thunderstorms, which continues to be supported by strong mid-level
   forcing for ascent.  But it is not clear that there will be more
   than a risk for localized strong surface gusts, aided by areas of
   enhanced downward momentum transport.

   ..Kerr/Hart.. 11/13/2021

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

   ATTN...WFO...BOX...

   LAT...LON   42137151 42477119 42197067 41946987 41167041 41627143
               41547124 42137151