US weather forecast: NWS warns of 'significant and dangerous' heat as forecasters predict it will begin over the weekend

Published 10 July 2026 · us

A vast and unusually intense heat dome is set to blanket most of the contiguous United States, driving temperatures to dangerous levels in what the

A vast and unusually intense heat dome is set to blanket most of the contiguous United States, driving temperatures to dangerous levels in what the Weather Service (NWS) has described as “significant and dangerous” heat. Forecasters said the heat wave will begin over the weekend and persist for at least a week, with some regions expected to endure above-normal temperatures through the end of the month. Daytime and overnight temperatures are forecast to run 15 to 25 degrees Fahrenheit (8 to 14 degrees Celsius) above seasonal averages in many areas. Elevated nighttime temperatures are expected to heighten health risks and make it more difficult to contain the country's already active wildfire season. Daniel Swain, a climate scientist with University of California Agriculture and Natural Resources, “This upcoming heat wave does look pretty remarkable. This is going to be a long duration, widespread and high-intensity heat event that’s going to affect millions of people for over a week.” A sprawling high-pressure system, often referred to as a heat dome, is expected to settle over the Northern Plains, trapping hot air much like a lid on a pot while preventing cooling winds and rainfall. However, meteorologists told The Associated Press that the system will be so expansive it could push sweltering temperatures across nearly two-thirds of the continental United States. Although the East Coast is expected to avoid the worst of the heat initially, forecasters said the heat dome is likely to shift and fluctuate over the coming days, potentially extending from coast to coast for more than 10 days.

Also Read | CEA advises against continuous use of air conditioners amid El Niño-driven heat Forecasters are expecting record triple-digit highs this weekend in Nevada, Utah, Colorado, Wyoming, Idaho, Montana, North Dakota and South Dakota. The weather service is predicting more than 90 US local temperature records will be tied or broken through Wednesday, with two-thirds being overnight heat records that can hinder how the human body recovers from broiling days. “Nights can be just as dangerous as days. If you don’t get heat relief at night, that’s going to spill out into your daytime experience and become extremely dangerous,” said meteorologist Bob Henson with Yale Climate Connections. “Heat is not to be played with. It’s just as dangerous as a tornado or hurricane that can kill you just as easily, just in a quiet and different way.” Swain said what makes this heat wave so different is how big a warm shadow it will cast and how long it will persist. Also Read | US braces for floods after storms, heat wave mar 250th anniversary celebrations In the past couple of weeks, major heat waves have caused extensive suffering in Europe, the US East Coast and most recently the U.S. Southeast. Now any place in the United States that escaped the earlier July heat waves will get this one, Swain said.