It will be warm and humid today with widely scattered showers and thunderstorms between 12 PM and 8 PM. The biggest threat for storms is west of a Boston-Providence line (per the NWS Special Weather Statement). A weak upper atmospheric disturbance will be the trigger for these showers and storms.
As of 8 AM, temperatures were in the mid 70’s in Central and Eastern Mass including the Cape and Islands. Temps are in the upper 60’s in Western Mass. Dew points are running in the upper 60’s to even 70 in a few locations (Marshfield, Norwood). Winds are generally out of the SW across SE MA (important) and calm elsewhere (also important).
Now and Noon
Temperatures will rise into the upper 80’s to near 90 by noontime. The SW wind off the water keeps Southern RI, the Cape and Islands and the immediate eastern coast in the low 80’s.
Dew points will rise into the upper 60’s in Southern Worcester County while dew points will be in the 70’s across much of SE Massachusetts. Dews will be in the low to mid 60’s in Western and Northern MA.
12 PM to 8 PM
Showers begin to pop up shortly before noon. Storms reach Northeast MA (including the Boston Metro) and Southern Worcester County by 230-3 PM. Rainfall will last into the evening commute in Northeast CT, Northern RI, and Central and Northeast MA. Rain will reach the South Connecticut and Rhode Islands coasts this evening. There will be a few strong thunderstorms with frequent lightning, heavy rain, and small hail. There will be some flash flooding and perhaps a few damaging wind gusts as well.
Some locations will see several rounds of showers and thunderstorms. The main cold front is back in the Midwest. There is very little steering away from Southeast MA, the Cape, and Islands. Often times we see a line of thunderstorms move along or ahead of a cold front and after the storms, temperatures and humidity drop. Is this one of those times?
We are going to do it all over again tomorrow, though perhaps the axis will be further west. Total rainfall today will be between 1-3″ where thunderstorms sit for an extended period of time. Temperatures will drop into the 70’s when the rain begins. There will be no relief from humidity until the cold front makes it through.