Posted by Chris Lambert
Low clouds and fog burn off early this morning and with hazy sun mixing in with the clouds, temps take off for the afternoon. Inland communities warm to near 90, while the coast reaches the mid 80s before the sea breeze kicks in. The Cape warms to the low to mid 80s. Many of today's hours are dry, however, with just enough instability in the atmosphere and a bit of "lift" from an incoming sea breeze, it appears scattered storms develop mid to late afternoon. I don't expect severe weather in terms of wind damage or large hail, but any thunderstorm will be capable of producing locally heavy rain. The overall chance of rain runs at 30%. Beach temps are 79-84 this afternoon, so it'll be a decent mid morning-early afternoon at the coast, just keep an eye to the sky anytime after 2PM.
The heat blasts in for most on Monday and sticks around all week with temps just away from the coastline running in the lower to middle 90s.
The westerly component to the wind isn't all that strong Monday-Wednesday, so we may indeed see sea breezes at this coast mid to late afternoon. That'll do two things: One, drop coast temps from the 86-90 range, back toward 80, if not even cooler at the beach. Two, act as enough lift to the atmosphere to spark an isolated thunderstorm across eastern Mass.
Thursday and Friday, west winds are strong enough to hold back the sea breeze, but any energy in the atmosphere sparks a thunderstorm for the afternoon. They'll be more widespread Friday and Saturday as a cool front approaches and eventually delivers relief by Sunday from the high humidity and heat.
So far this year we've had 10 days total at or above 90 degrees in Boston and officially 2 heat waves (3 consecutive days of 90+). It'll be interesting to see in the city if one or two days falls just shy of 90 next week thanks to an early afternoon sea breeze. That would be the only way to avoid our 3rd heat wave of the year in the city. I don't think we'll avoid that around the I-95 belt and through most of Metrowest as a sea breeze is too far removed.
Stay cool, have a good Sunday!