Boston Weather Today: Heatwave and Severe Thunderstorms Possible—Your Hour-by-Hour Forecast

Boston woke up under a rare Excessive Heat Warning this morning as the city’s first official heat wave of 2025 barrels into a potentially record-setting third day. Meteorologists say the mercury could flirt with 102 °F at Logan Airport this afternoon—Boston’s hottest June temperature since 1952—while a “feels-like” index near 110 °F will blanket much of Suffolk, Middlesex, and Essex Counties. Current conditions • 10 a.m. temperature: 97 °F, humidity 40 %, west wind 12 mph • Peak heat window: 1 p.m.–5 p.m.; air quality alert in effect for ground-level ozone • Chance of precipitation: <5 % through sunset Why it’s historic Boston typically logs only one 100 °+ day every decade. Reaching triple digits in late June is even rarer, happening just twice in the last 75 years. According to Boston.com, today’s dome of subtropical high pressure could nudge past the all-time June record of 100 °F set on 6/22/1952. When will the heat wave end? • Wednesday: A weak cold front slides through before dawn, trimming highs to the lower 90s with slightly lower humidity. • Thursday: Northeasterly winds off the Atlantic slash daytime temperatures to the upper 60s—an almost 35-degree plunge—along with scattered showers. • Friday–Sunday: Mostly cloudy skies keep readings in the mid-60s to mid-70s, but another warm surge is likely early next week as the jet stream retreats north. Hourly cooling trend 2 p.m.: 102 °F 5 p.m.: 100 °F 8 p.m.: 88 °F 11 p.m.: 81 °F Health and safety checklist • Hydrate: Aim for 16–20 oz of water per hour if working outdoors; avoid alcohol and sugary drinks. • Seek shade: City-run cooling centers are open 9 a.m.–8 p.m.; find the nearest location via 311. • Check vulnerable neighbors: Anyone over 65, under 5, or with heart/lung conditions faces higher heat-stroke risk. • Pet care: Asphalt can exceed 150 °F—walk dogs before 9 a.m. or after 7 p.m. Transit impacts The MBTA has instituted “heat order” speed restrictions on Red and Orange Line tracks; commuters should plan for 10–15-minute delays during the afternoon rush. Amtrak says concrete tie inspections may slow Northeast Corridor trains by up to 30 minutes. Climate context Boston now averages seven more 90 °F days per summer than it did in 1970, and climate-model projections indicate the city could see 20–30 such days annually by 2050. Urban heat-island studies show inner neighborhoods like Roxbury and Dorchester routinely run 8–12 °F hotter than coastal communities, underscoring the need for expanded tree canopies and reflective roofing programs. Bottom line Today’s extreme Boston weather is dangerous, not just uncomfortable. Limit strenuous activity, monitor real-time forecasts, and prepare for rapid cooling by mid-week. Stay weather-aware—this heat wave may be short-lived, but a hotter-than-normal summer is only just getting started.