BOX
It looks like the more active of the two days appears to be on
Thursday, as a fairly strong trough in prevailing quasi-zonal flow
moves across the Great Lakes into northwest NY. This will spread a
cold front across much of New England, with at least scattered
thunderstorms to develop along and ahead of the front. The better
upper support mostly passes to our north. However noted the still
fairly strong unidirectional wind fields with related speed shear
contributing to effective bulk shear values around 40 kt, with LI`s -
4 to -7C and most-unstable CAPEs ranging from 1500 to 2500 J/kg. A
few stronger storms certainly possible and severe is not out of the
question given the above favorable shear-instability parameter
space. Potential for localized torrential downpours as well, but
fairly fast storm motions could limit the duration of torrential
rain. There are the mesoscale details that need to be narrowed down
a bit more, but from a synoptic standpoint Thursday will need to be
watched. Leftover thunder should move off the coast of SE MA before
midnight on Thursday night, with cooler and increasingly drier air
filtering in by early Friday.
BOX It looks like the more active of the two days appears to be on Thursday, as a fairly strong trough in prevailing quasi-zonal flow moves across the Great Lakes into northwest NY. This will spread a cold front across much of New England, with at least scattered thunderstorms to develop along and ahead of the front. The better upper support mostly passes to our north. However noted the still fairly strong unidirectional wind fields with related speed shear contributing to effective bulk shear values around 40 kt, with LI`s - 4 to -7C and most-unstable CAPEs ranging from 1500 to 2500 J/kg. A few stronger storms certainly possible and severe is not out of the question given the above favorable shear-instability parameter space. Potential for localized torrential downpours as well, but fairly fast storm motions could limit the duration of torrential rain. There are the mesoscale details that need to be narrowed down a bit more, but from a synoptic standpoint Thursday will need to be watched. Leftover thunder should move off the coast of SE MA before midnight on Thursday night, with cooler and increasingly drier air filtering in by early Friday.
