The most dangerous heat wave in years is bearing down on the entire Northeast corridor this Fourth of July week, with Extreme Heat Warnings covering all of southern New England, the New York metropolitan area, Long Island, the Hudson Valley, New Hampshire, southwestern Maine and Vermont’s Lake Champlain corridor — and forecasters warning that “this is a prolonged and dangerous heatwave with little relief at night.”
The worst heat index values — up to 115°F — will arrive Thursday and Friday, the peak of a heat event that has already put 162 million Americans under heat alerts from the Great Plains to the Atlantic coast, according to the National Weather Service.
The Warning Package: Five States, Five NWS Offices
Massachusetts, Connecticut, and Rhode Island (NWS Boston): Warning runs 10 AM Wednesday through 8 PM Saturday — covering Boston, Worcester, Springfield, Lowell, Lawrence, Cambridge, Brockton, Quincy, Fall River, New Bedford, Framingham, Providence, Newport, Warwick, Hartford and Windsor Locks. Heat index values of 98 to 115°F are expected. Boston could see actual temperatures of 100°F Thursday — a threshold the city has crossed only 28 times in its entire recorded history.
New York City, New Jersey, and Southern Connecticut (NWS New York): Extreme Heat Warning through 9 PM Friday with heat index values of 110 to 115°F for the NYC metro, Long Island, Westchester, Rockland, and Bergen/Passaic/Essex/Union counties in NJ — followed by an Extreme Heat Watch through Saturday. NYC could experience back-to-back 100-degree days for the first time since 2011. The NWS New York office warned that “this level of heat can be deadly for those without adequate cooling and hydration” and flagged possible impacts to transportation infrastructure and electrical and water systems.
Hudson Valley, Capital Region, and Taconics (NWS Albany): Warning through 8 PM Friday — heat index 105-110°F — for Albany, Schenectady, Troy, Poughkeepsie, Kingston, Saratoga Springs, the Berkshires, Litchfield County CT, Bennington VT and the Mohawk Valley. Overnight lows in the 70s both Wednesday and Thursday nights.
New Hampshire and Southwestern Maine (NWS Gray): Warning through 8 PM Friday — heat index up to 111°F — for Manchester, Nashua, Concord, Portsmouth, Dover, Keene, Laconia, Portland, Lewiston, Biddeford and Saco. “Overnight low temperatures will only fall into the 70s, resulting in accumulated heat stress.”
Vermont and Plattsburgh, NY (NWS Burlington): Warning through 7 PM Friday — heat index up to 106°F — for Burlington, Middlebury, Rutland, Plattsburgh, St. Albans, White River Junction and the full Lake Champlain corridor.
July 4th Weekend and America’s 250th Birthday
This heat wave is arriving at the most symbolically significant July 4th in American history — the 250th anniversary of the Declaration of Independence, with massive celebrations planned in Philadelphia, Washington, New York and Boston. Philadelphia has declared a heat emergency Wednesday through Saturday, opened 50 cooling centers, is moving parts of the FIFA World Cup Fan Festival into cooled tents, and has shortened its Independence Day Parade by one mile. Washington, D.C. could see three consecutive days of 100-degree temperatures at the focal point of America 250 celebrations on the National Mall.
The NWS forecast discussion called this “a potentially historic heatwave across the eastern third of the country,” with the possibility of all-time record highs in some locations Thursday and Friday.
What Staying Safe Means for Four Days of Extreme Heat
This is not a single-afternoon event. “The heat stress will compound day after day,” said Dr. Kisha Davis, health officer for Montgomery County, Maryland. Overnight lows in the 70s don’t give the body a chance to cool down naturally — that cumulative effect is what turns extreme heat from dangerous to deadly, particularly for elderly residents, people without air conditioning, and outdoor workers.
The NWS Albany office reminded residents: if you do not have air conditioning, call 211 for assistance locating appropriate cooling shelter. Do not leave children or pets in unattended vehicles. Heat stroke — hot, red, dry skin; rapid pulse; confusion — is a 911 emergency.
Monitor the latest updates at weather.gov/box (Boston), weather.gov/okx (NYC), weather.gov/aly (Albany) and weather.gov/gyx (NH/ME).
