In today's "Chat With Matt" on Facebook, Marc Arvilla asked: "Hi Matt, what do you think the risk of severe weather will be on Saturday and will there be a tornado threat for Mass?"
Great question, Marc. I'm concerned about damaging storms on Saturday because both the upper level pattern and surface setup support strong thunderstorms with the potential for damaging wind. Additionally, an abundance of moisture (humidity) in the atmosphere will raise the risk for some localized flash flooding. That said, for the Southern half of New England, the storms would likely wait until late day and evening, while an earlier scenario would play out for Central New England, and Northern New England would likely see just morning showers. Some inside baseball: the maps below show forecast available thunderstorm energy at 2 PM Saturday on the left (prior to storm development in Southern New England, during storms in Central New England), and the tendency for air to spin as it rises, on the right., valid at 5 PM, when storms would probably be pushing into Southern New England. Notice a lot of energy, but the areas favoring spin are pretty limited. This suggests damaging storms, but rather confined areas of potential tornado development. Will keep watch, for sure, to see how, if at all, these parameters change: