Most of America’s Lower 48 states are about to swelter under an unusually large, strong and long-lasting heat dome that will spike temperatures in a way that the National Weather Service calls “significant and dangerous.”The heat wave will start this weekend and last at least a week, with some areas feeling its effects until the end of the month, meteorologists said. Temperatures will be 15 to 25 degrees Fahrenheit (8 to 14 degrees Celsius) warmer than normal in many areas, including at night, they said. Hotter nighttime temperatures are especially bad for both human health and efforts to tamp down an already active wildfire season.”This upcoming heat wave does look pretty remarkable,” said Daniel Swain, a climate scientist with University of California Agriculture and Natural Resources. “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.”Trapping hot air, threatening recordsA dome of high pressure — which traps hot air like a pot lid while blocking cooling winds and rain — will initially park over the Northern Plains, but it will be so big that it will trap sweltering temperatures across as much as two-thirds of the continental United States, three meteorologists told The Associated Press. While it will initially miss the East Coast, the heat dome will shift and wobble, maybe even spreading from coast-to-coast over the next 10 days or more, they said.AdvertisementAdvertisementForecasters 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 U.S. local temperature records will be tied or broken through Wednesday, with two-thirds being overn …
