New England remains in a repetitive weather pattern for the last half of the week, with overnight and morning stretches of clouds and fog breaking for a blend of sun and clouds with isolated to widely scattered sprinkles and light showers popping up during the middays and afternoons as temperatures rebound into the 70s.
This pattern holds through Friday, when, yet again, pockets of clouds will start the day but sun will emerge and some inland communities will touch 80° by afternoon.
The pattern of scattered sprinkles and showers will end Saturday, as a stubborn and large storm center that’s been stalled southeast of New England nudges east and allows a change in the jet stream winds aloft – the fast river of air, high in the sky, that steers storms and separates cool air to the north from warm to the south. With the change in the jet stream will come a sea change of air – new, warm, humid air arrives Saturday with high temperatures boosted into the 80s regionwide with some inland communities touching 90 in the afternoon as a sea breeze kicks up at the coast after our beaches reach the 80s.
Sunday looks similar, with a continued increase in humidity but no sufficient trigger for thunderstorms in most of New England, except in the mountains of northern New England where an isolated Sunday afternoon storm may pop up from “differential heating” – a difference in temperature from mountaintop to valley that can serve to initiate isolated storms.
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Monday brings a more widespread storm instigator: A cold front crossing New England from northwest to southeast that will be slow enough for most of the six-state region to experience another very warm and humid day, but prompting a number of showers, downpours and thunderstorms.
Behind the cold front, less humid and cooler air sets up for Tuesday, when an early shower can’t be ruled out but the trend should be toward drying and fair weather through the middle and end of next week, when heat and humidity will start a return to New England.
The start of the July 4 holiday weekend is on the 10-day forecast and right now our First Alert Team expects the weekend to start with temperatures in the 80s, humidity and a chance of thunderstorms, but we’ll continue to roll out the rest of the holiday weekend in the two days ahead.