Boston started the week on a deceptively calm note Monday, with mostly clear skies and temperatures at Logan Airport holding around 61°F early in the morning. The city can expect a mostly sunny afternoon with a high near 71°F, with the immediate waterfront staying a bit cooler than inland neighborhoods. The quiet start will not last long, though, as a sharp warm‑up charges in by midweek and cranks up the heat across much of southern New England.
Midweek Heat Watch
According to the National Weather Service Boston/Norton, Tuesday will feel like someone flipped the switch to July. Boston proper is forecast to top out near 88°F, while interior communities could surge into the mid‑ to upper‑90s. Those readings put parts of southern New England in record range, with Boston's mid‑May daily record sitting around 90°F. If you are planning to be outside, treat it like true summer: keep water handy, avoid the midday sun, and schedule strenuous activity for the morning or evening.
Storms And Gusty Winds Possible
The risk of rain Tuesday afternoon is low, limited to a slight chance of spotty showers. That changes on Wednesday, when a frontal system approaches and the atmosphere gets more unstable. The day should start off hot, with a high near 92°F, then turn showery and breezy by afternoon and evening. A few thunderstorms could pack a punch, with strong, damaging wind gusts and brief heavy downpours in the mix. If you have outdoor plans later Wednesday, it is smart to have an indoor backup and keep an eye on local alerts.
Coastal Relief And Marine Outlook
Not everyone will bake equally in this pattern. Coastal neighborhoods will catch a sea breeze that holds readings in the 70s to low‑80s, while inland spots roast in the full heat. On the water, mariners should plan for seas to build to roughly 4–6 feet and for southerly winds to increase from Tuesday into Wednesday. Small Craft Advisories may be needed Tuesday night into Wednesday on exposed waters. If you are heading out on the harbor, secure loose gear and check for marine notices before leaving the dock.
How To Stay Safe
The City of Boston keeps an updated list of cooling centers and heat‑safety guidance, so check the City of Boston cooling resources for maps and opening details if you need a cool place. The city's emergency page also includes tips for older adults, children and people without air conditioning. Never leave children or pets in parked cars, drink plenty of fluids, and check on neighbors who may be more vulnerable in the heat.
Quick Forecast
Today: Mostly sunny, high near 71°F. Tonight: Mostly clear, low near 61°F. Tuesday: Hot, upper 80s to low 90s with inland areas hotter, slight chance of afternoon showers. Wednesday: Hot early, then showers and a higher chance of thunderstorms with cooler, breezy conditions Thursday.
