An amplifying shortwave trough with associated cold front at the surface traverse the Northeast Friday. Ahead of the approaching cold front, temperatures are expected to warm into the 70's and 80's with dewpoints climbing into the 60's. This should result in mixed-layer CAPE values ranging anywhere between 1,000-1,500 J/KG by peak heating. While there is potential for a narrow corridor of values in the 1,500-2,000 range, weak mid-level lapse rates will limit how unstable the atmosphere will become. Associated with the approaching shortwave trough will be seasonably strong dynamics characterized by 30-35 knots of bulk shear.
Given the combination of modest instability, adequate deep layer shear, and strong forcing, scattered thunderstorms should develop by mid-day across central New York southwest into Pennsylvania. Given shear will become parallel to the front, convection should grow upscale into a line and then slowly sag southeast through the remainder of the afternoon and early evening. While low-level winds aren't overly impressive, the combination of steep lapse rates and unstable low-levels will yield the risk for damaging wind gusts within the strongest cells. Higher 0-3km helicity values may result in the potential for some small hail with any transient supercell structures and storm motion parallel to the front will yield potential for localized flash flooding, particularly in low-lying, flood prone areas.
Best chance for strong thunderstorms will be across southern Vermont, southern New Hampshire, western Mass, and northwest Connecticut.