A strong upper level low sitting over the Great Lakes is providing a cold pool aloft with 500mb temperatures around -15C. The low is generating a 40kt mid level southwesterly jet across the northeast while a 995mb surface low produces southerly / south-southeasterly flow into southern New England. Abundant low level moisture combined with periods of sunshine tomorrow will destabilize the atmosphere with afternoon surface CAPE of 1000J/kg to 1500J/kg. This is a classic set up for a round of strong to severe thunderstorms to the southeast of the upper low, intersecting the low level jet. In this case, the severe threat area extends across most of New York State into western and southern New England.

With the deep cold pool aloft, the primary threat with any thunderstorms will be large hail. Damaging wind gusts are also possible and depending on the extent of the easterly component on the low level winds, we could see a tornado or two develop.