Boston's way-too-early triple-digit heat wave
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Massachusetts is in the midst of its inaugural heat wave of 2025, with extreme heat warnings extending through Tuesday evening as temperatures reach dangerous levels.
Why it matters: It's 2025's first official heat wave, defined as three consecutive days of 90+ degree temps, and many just aren't ready for this kind of brutal hellscape in late June.
- It could be potentially life-threatening for vulnerable populations if they don't take it seriously or think the heat gets nasty only in August.
What they're saying: "This is the first big heat wave of the summer, and that always means that people are caught unawares a little bit," Boston University School of Public Health Associate Professor Dr. Patricia Fabian told Axios.
- Fabian said people might not have acclimated to such high temperatures this early in the summer.
Zoom in: Tuesday afternoon will be the peak of the danger. National Weather Service forecasters warn of "extreme" heat risk.
- Heat index values are forecast to reach 105-110 degrees.
- Actual temperatures could hit 96-102 degrees across the region.
- Overnight temperatures may drop to near 80 degrees downtown, not nearly low enough for relief.
Threat level: Fabian said blackouts caused by high power consumption during the heat wave could lead to further safety risks for anyone who relies on mechanical cooling.
- "We're expecting more people to get sick, heat stress, more people to show up at the hospital and more people probably to die," Fabian said.
Fabian said people should prepare for extraordinary heat with the same care they would prepare for a blizzard.
- "That means making sure you have water available, making sure that if you're outside, you're taking breaks in the shade," Fabian said.
- She recommends putting together a cooling kit with powdered electrolytes and an ice pack if you're going to be outside in the heat.
The bottom line: Municipal officials have activated cooling centers and urge residents to limit outdoor exposure during the most intense heat period Tuesday.
What's next: A "cold front" should arrive Tuesday night with scattered thunderstorms that should drop temperatures to the 70s.