The “main event” with this system will come tomorrow night probably between the hours of 8PM and 2AM. A squall line is likely to form well to the west of Route I-95 late tomorrow afternoon extending in a north-to-south fashion from central NY-to-central PA-to-western Virginia. This squall line is likely to arrive in the I-95 corridor between the hours of 8PM to 2AM with downpours, strong-to-severe thunderstorms, and wind gusts to 50 mph or so. Power outages are on the table as many leaves remain on trees which makes them more vulnerable than say a month from now. Behind the front, winds will turn to a west-to-northwest direction and can gust past 40 mph towards Friday daybreak. In terms of total rainfall, there will be a tendency for lesser amounts as one goes from west-to-east with central and NE PA, for example, likely to receive 1.5 – 2.0 inches, around an inch in the immediate I-95 corridor, and about half an inch at the NJ/Delmarva coastlines.

Widespread freeze possible on Sunday night

Temperatures so far this season have not dropped to the freezing mark in many parts of the I-95 corridor, but that is likely to change after this frontal passage. While there is a decent chance for some near freezing temperatures late Friday night and late Saturday night, an even better chance is likely to come late Sunday night. In fact, with the coldest air of the season arriving on Sunday, the stage will be set for the first widespread freeze late Sunday night/early Monday as signs point to excellent conditions for radiational cooling (i.e., clear skies, diminishing winds) with high pressure moving directly overhead.