100 million Americans expected to be under dangerous heat this week

Key Points:

• Dangerous heat is forecast to impact over 100 million Americans this week, with record-breaking temperatures in Western cities such as Salt Lake City (109°F), Billings (111°F), and Miles City (115°F), shattering previous all-time highs.
• A heat dome over the Northern Plains is causing extreme heat and humidity, with heat warnings from Utah to Michigan and heat indices reaching up to 110 in places like Fargo, North Dakota, and Zion Canyon, Utah.
• The Northeast will experience a heat wave starting Tuesday, with multiple days above 90°F and heat indices near or above 100 in major cities including New York City, Philadelphia, Washington D.C., and Boston.
• Southern California is under heat alerts through Thursday, with interior valleys reaching up to 105°F and downtown Los Angeles temperatures rising into the mid to upper 90s later in the week.
• A severe weather threat is expected Tuesday afternoon and evening in northern New England due to a cold front interacting with heat and humidity, with risks of destructive winds, large hail, and possible tornadoes in areas including northern Vermont, New York, New Hampshire, and Maine.