(NEW YORK) — Dangerous heat from Los Angeles to Boston is expected to impact more than 100 million Americans this week.
Multiple cities in the West, from Utah to Montana, experienced their hottest temperatures on record Sunday afternoon, shattering previous heat records.
The preliminary high temperature in Salt Lake City was 109 degrees F, breaking the previous all-time record high of 107 degrees, previously set in 1960, 2002, 2021, and twice in 2022. Temperature records for the city go back to 1874.
Billings, Montana reached a preliminary high temperature of 111 degrees on Sunday afternoon, shattering the previous all-time high of 108 degrees set on July 14, 2002.
In Miles City, Montana, the temperature rose to a preliminary high of 115 degrees on Sunday afternoon, also shattering its previous all-time high of 111 degrees set on June 26, 2012.
For reference, the hottest temperature ever recorded in the state of Montana is 117 degrees, observed in the town of Medicine Lake on July 5, 1937, and in Glendive on July 20, 1893.
A heat dome has set up over the Northern Plains, with extreme heat and humidity over America’s northern tier.
An extreme heat warning is in place through Thursday for Minneapolis, Minnesota, with daily high heat index up to 100 possible.
Other extreme heat warnings are in place from Utah to the upper peninsula of Michigan.
In Utah, places like Zion Canyon could feel like 110 today, while Salt Lake City and Billings reach above 100.
Fargo, North Dakota, is under an extreme heat warning for a heat index as high as 110 today and Tuesday.
The heat index for places like Calumet, Michigan, and Duluth, Minnesota, could reach near 100.
On Tuesday, Detroit, Michigan, is under an extreme heat watch for a heat index near 107.
In the Northeast, a heat wave is set to begin on Tuesday, with three or more days of temperatures over 90 degrees for New York City, Philadelphia and D.C.
A heat advisory is in place for at least Tuesday and Wednesday across much of the Northeast due to heat indices around 100 expected.
The upper Northeast will be hottest on Tuesday with a heat index of 100 to 104 from Rochester to Albany to Boston.
New York City to D.C. is likely the hottest on Wednesday with heat indices near 100 in NYC and near 105 in D.C.
Out West, Southern California is under heat alerts through Thursday.
Temps will reach 85 to 90 across the coastal valleys and up to 105 for the interior valleys through Tuesday.
Wednesday and Thursday will be hotter, with temps in downtown LA reaching the middle to upper 90s and interior valleys reaching up to 105.
Tuesday severe weather threat for northern New England
Fueled by the extreme heat and humidity and a sinking cold front from Canada, severe storms capable of destructive winds over 70 mph, large hail large than ping pong balls and a strong tornado or two will move over northern New England.
A level 3 of 5 risk is in place from northeast New York through northern Vermont, northern New Hampshire, and northern Maine on Tuesday afternoon and evening. It includes Burlington, Vermont; Plattsburgh, New York; Caribou, Maine; Colchester, Vermont; and Massena, New York.
Storms are most likely after 5 p.m. ET and continuing into the night as the cold front sinks south.
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