A relentless heat wave that has been sending temperatures into the triple digits and has put roughly a quarter of the U.S. population under a heat advisory is not showing any signs of letting up, with dangerous levels of heat forecast for the South, the Southwest and South Florida, according to the National Weather Service.
People can expect record-breaking heat through the middle of the week from Texas to the lower Mississippi Valley, according to the Weather Service.
More than 70 million people across the country were facing dangerous levels of heat as of Monday morning, according to a New York Times analysis of current Weather Service advisories and LandScan population data.
Phoenix has experienced two weeks of 110-degree days — one of its longest ever such stretches — as a “heat dome” set records across the Southwest over the weekend.
The city also recorded the longest number of days in a row — eight — with low temperatures in the 90s, the National Weather Service in Phoenix said on Monday. The low on Monday morning was 95 degrees, the service said.
In South Florida, the Weather Service on Monday also warned of low temperatures of 90 degrees, with the heat index expected to approach 105 to 110 degrees. The heat index measures how hot it feels outside, accounting for temperature and humidity.
For those seeking to cool off, there will be little opportunity to do so in the places hit hardest by the high temperatures, with particularly high daily minimum temperatures.
Aside from the heat, other parts of the country are facing additional severe weather alerts, notably for rain. “Severe storms and bouts of heavy rain to occur from the Nation’s Heartland to the Ohio Valley and Northeast through Tuesday,” the Weather Service warned.
The Northeast already saw heavy rainfall and flash flooding over the weekend. In Pennsylvania, sudden rains struck parts of Bucks County, north of Philadelphia, killing at least five people and trapping others in their cars. In one part of Long Island in New York, five inches of rain fell in less than two hours.
“We are in a very, very unstable weather condition,” Kathy Hochul, New York’s governor, said. “Your car can go from a place of safety to a place of death.”
And if that wasn’t enough, smoke from the ongoing wildfires in Canada will again affect the United States this week and could trigger air quality alerts over parts the Northern High Plains, the Midwest, the Great Lakes and the Northeast.
There’s one pocket of the country that seems exempt from the scorching heat: The Midwest and the Great Lakes are in the middle of a cold front that will cause cooler than normal temperatures, with some locations struggling to get out of the 70s for the beginning of the week, according to the Weather Service.
Heat can be particularly devastating to people who are already suffering from health conditions. In the Phoenix area, for example, there have been 12 reported heat-related deaths through mid-June, and 40 more open cases where heat is being investigated as a factor, according to the Maricopa County medical examiner. Hundreds of people die from extreme heat in the United States every year.
To stay safe on extremely hot days, the Weather Service advised people on Monday to drink plenty of fluids, stay in cooler rooms, stay out of the sun and check on relatives and neighbors, especially older people who live alone.
“Wear light-colored clothing,’’ Ken Graham, director of the National Weather Service, said on Twitter on Monday. “Loose fitting helps as well.”
Johnny Diaz contributed reporting.