The Boston area saw weaker showers and storms Tuesday, but will be right in with the rest of the New England on Wednesday afternoon for scattered strong to severe thunderstorms.
The upper atmospheric energy that’s been driving the unsettled weather across New England since Sunday is sitting directly overhead Wednesday morning, delivering some scattered morning showers and downpours amidst breaks of sun.
That limited sun will warm the air, coupled with lingering humidity, to add “instability” to the atmosphere. The increased energy creates favorable conditions for thunderstorm development, breeding thunder from midday onward, with the strongest during our First Alert time of 1 p.m. to 8 p.m.
Heavy rain and frequent lightning are likely with all storms, meaning pockets of street flooding and perhaps isolated flash flooding will be possible. It's important folks outside keep shelter nearby in case a storm comes calling with a lightning risk.
Stronger thunderstorms Wednesday afternoon will drop hailstones – balls of ice at the center of storms – and produce some localized bursts of damaging wind. Showers will diminish overnight Wednesday night with partial clearing and patches of fog giving way to sunshine Thursday.
Most of the day through middle afternoon will be storm-free, so sunshine and humidity will result in high temperatures rising from 85 to 90 degrees with a heat index around or over 90 for many!
After plenty of sun, a late day disturbance Thursday will raise the chance of scattered showers and thunder in northern, then central New England. The storms will eventually reach southern New England Thursday evening and night but likely to remain scattered.
The scattered late Thursday storms come ahead of a wind shift that will turn an onshore wind into New England. This should make Friday much cooler and less humid for all, except perhaps Cape Cod, with highs generally in the 70s. The air will be noticeably more comfortable, likely forcing any chance of focused showers and thunder far west, perhaps all the way into New York.
The Fourth of July is expected to be pleasant and seasonable with highs around 80 and not much humidity. Sunday looks great, too. If you’re a fan of mid-summer warmth, it should return for most of next week in our exclusive First Alert 10-day forecast.