boston Much of New England is bracing for a prolonged period of dangerously high temperatures as a powerful heat dome looms over the Northeastern United States. Forecasters warn that temperatures could approach or exceed 100°F during the July 4th holiday, while humidity will push heat indexes as high as 105°F to 110°F in some areas.
The National Weather Service has issued an extreme heat warning for Massachusetts and much of New England, except Cape Cod and the Berkshires, from Wednesday morning through Saturday.
Meteorologists warn that the combination of extreme heat and tropical humidity could pose serious health risks, especially for the elderly, children and people who work outdoors.
Forecasters say Tuesday will be the most comfortable day of the week, with highs ranging from the upper 70s near the coast to the upper 80s inland.
Map: Heat expected to peak before Independence Day
NBC Boston meteorologists expect Thursday and Friday to be the hottest days of the week. Temperatures could rise to around 100°F in parts of Massachusetts, with heat indexes between 105°F and 110°F possible.
The National Oceanic and Atmospheric Administration’s heat risk outlook categorizes much of greater Boston as being at “extreme” heat risk through Thursday.
Combined with increased humidity, the weather can create hazardous outdoor conditions. Nighttime temperatures are also expected to remain warm, limiting relief.
What is a thermal dome?
The heat wave is part of a broader “heat dome,” or high-pressure system, that stretches from the central United States to the East Coast, The Boston Globe reported.
High pressure causes the air to sink, which causes the air to heat up. When high pressure exists over a location, warming becomes more pronounced every day, and this week is no different.
Temperatures could hit record highs in region
Boston could challenge multiple daily temperature records during the heat wave. According to the Boston Globe, the high temperature is expected to be about 102°F on Thursday, which will exceed the current daily high temperature record of 98°F. The city’s all-time high temperature remains 104°F, set on July 4, 1911.
Health officials urged residents to drink plenty of fluids, avoid strenuous activities in the afternoon, wear light clothing and not leave children or pets in parked vehicles.
A cold front is expected to move through the area late Thursday or early Friday. This system could bring scattered showers or thunderstorms ahead of the arrival of cooler, moist air for part of the July 4th holiday.
