Mesoscale Discussion 1722
NWS Storm Prediction Center Norman OK
1125 AM CDT Fri Aug 26 2022
Areas affected...far eastern New York into parts of New England
Concerning...Severe potential...Watch possible
Valid 261625Z - 261830Z
Probability of Watch Issuance...60 percent
SUMMARY...Scattered strong storms will develop after 17Z, moving
from eastern New York into parts of New England. A few damaging
gusts are most likely, and a weak/brief tornado cannot be ruled out.
DISCUSSION...Surface analysis shows a low developing over far
eastern NY, and just south of an early-day cluster of thunderstorms
which stretches into VT. Meanwhile, a diffuse warm front extends
eastward toward far southern ME, though mixing may lead to a
northward repositioning later today.
Heating and advection of mid to upper 60s F dewpoints has led to an
uncapped and unstable air mass, with CAPE presently in the 1000-2000
J/kg range. The strongest instability currently exists over southern
New England where dewpoints are higher. Further, GPS PWAT sensors
show a marked increase in overall moisture values through a deeper
layer, approaching 1.50" near coastal CT.
Convergence near the developing surface low and trailing surface
trough and continued heating will lead to increasing storm coverage
throughout the afternoon, progressing eastward. Deep-layer shear
averaging near 35 kt, as well as veering winds with height suggest a
several storms may be severe, producing a combination of damaging
gusts and isolated hail. Steepening low-level lapse rates, and moist
boundary layer, and weak SRH values could support a brief/weak
tornado with the stronger isolated cells.
..Jewell/Thompson.. 08/26/2022