Mesoscale Discussion 1629
   NWS Storm Prediction Center Norman OK
   1236 PM CDT Sat Aug 29 2020

   Areas affected...Portions of NY...VT...and western NH/MA/CT

   Concerning...Severe potential...Watch likely 

   Valid 291736Z - 291930Z

   Probability of Watch Issuance...80 percent

   SUMMARY...The threat for damaging winds, a couple tornadoes, and
   marginally severe hail should increase this afternoon. Watch
   issuance is likely.

   DISCUSSION...Storms will continue to increase in coverage this
   afternoon across much of central/eastern NY as a large-scale upper
   trough moves eastward from the Great Lakes across the Northeast.
   Widespread cloudiness has hampered diurnal heating so far, but some
   breaks in the clouds have recently been noted across western NY
   along/ahead of a cold front. Although mid-level lapse rates should
   remain modest, MLCAPE of 500-1500 J/kg should become common by peak
   afternoon heating. Strong mid-level winds associated with the upper
   trough (40-50 kt) and a veering wind profile through low/mid levels
   will support 35-45 of effective bulk shear, and supercells appear
   possible. In fact, a low-topped thunderstorm near Albany NY has
   recently acquired some low-level rotation given this favorable wind
   profile. Current expectations are for additional supercells to form
   across central NY over the next couple of hours, and then move
   eastward into parts of western New England as the airmass slowly
   destabilizes across these areas. At least isolated damaging wind
   gusts and marginally severe hail may occur with these storms. A
   couple tornadoes also appear possible, mainly across eastern NY into
   southern VT and western NH/MA/CT, where effective SRH may locally
   reach 100-150 m2/s2. Watch issuance will likely be needed within the
   next couple of hours to address this increasing severe threat.

   ..Gleason/Grams.. 08/29/2020

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

   ATTN...WFO...GYX...BOX...BTV...OKX...ALY...BGM...

   LAT...LON   43587511 44127418 44097228 43327176 42947187 41507321
               41507444 42187558 42767607 43587511