by -
A dome of heat settled over the central and eastern US this week, potentially causing three deaths.
-
The heat closed schools and killed some 2,000 head of cattle. It is expected to continue next week.
-
Forecasters expect this summer to see above-average temperatures across most of the US.
It’s been a hot week for millions of people in the US and it’s not over yet.
A heat wave has broken daily temperature records in the Southwest, Central Plains and Midwest this week. More than 100 million people in the US have been under some form of heat alert and have been advised to stay indoors.
Two people have died in the Milwaukee area amid the extreme temperatures: a 39-year-old woman found in her home and an 89-year-old man who collapsed in his yard. The medical examiner’s office said they were “probable” deaths from heat, according to NBC News. Another man, 67, was found dead in California’s Death Valley National Park after running out of gas and walking in the heat.
Tens of thousands of people suffered power outages. School districts in Michigan have canceled classes and public schools in Pittsburgh, Pennsylvania, have switched to half-days to avoid the hottest hours, ABC News reported. In Odessa, Texas, a water main broke, leaving residents enduring the heat without running water for more than 48 hours, The Texas Tribune reported.
In Kansas, some 2,000 head of cattle have died from heat stress as of Tuesday, according to Reuters.
“It’s really a combination of heat and humidity that’s causing some of these impacts,” Marc Chenard, a meteorologist with the National Weather Service, told Insider. “It really depends on how used these areas are to that kind of weather, and also what time of year it is. So for some parts of the country, it might be a little early for some of this heat and humidity.”
Humidity can make extreme temperatures feel even hotter, as it hinders the cooling process of sweat that evaporates from people’s skin. That’s why humidity can increase the heat index 10 to 15 degrees above the actual temperature.
Milwaukee’s heat index reached a Registration June high of 109 degrees Fahrenheit on Tuesday. Las Vegas also reported 109 degrees. North Platte, Nebraska, got its own June record high of 108 degrees. Phoenix, Arizona, rose even higher to 114 degrees. Death Valley beat them all by 123 degrees.
The heat is likely to continue into next week in many parts of the US, according to forecasts from the Weather Prediction Center, operated by the NWS and the National Oceanic and Atmospheric Administration. The following map shows the projections of the center.
“The prolonged nature of the well above normal temperatures and excessive heat has been impressive in early to mid-June,” Chenard said.
The Climate Prediction Center also produces a three-month outlook for temperatures across the country. That forecast projects a summer of above-average heat across the United States, with the exception of two small pockets in the north.
“I don’t think we’re going to have record temperatures every day or every week through the summer. But I think what this suggests is that conditions will be favorable to see at least rounds of temperatures well above normal at times during the summer,” Chenard said.
Heat waves are becoming more common, severe and prolonged as global temperatures rise. The 2018 National Climate Assessment found that the frequency of heat waves has tripled since the 1960s and that the average heat wave season has increased by 45 days.
A ‘heat dome’ with tornadoes and thunderstorms around
This month’s extreme temperatures came from a “heat dome,” a ridge of high pressure in the upper and middle layers of the atmosphere, trapping heat below it. The dome started in the Southwest and then parked over the central and eastern US.
“In this case, it just persisted for a long time,” Chenard said, adding, “We just have this bubble of heat that has been over the central part of the country.”
In Chicago, the heat wave came along with gale-force winds and a rare instance of a circulation system threatening to become a tornado over the city. Two large tornadoes hit central Wisconsin this week, according to the La Crosse Tribune.
It’s not clear if the tornadoes were directly related to the heat wave, but Chenard said storms typically form around the boundaries of heat domes, where they interact with other weather systems.
“It’s common for rounds of thunderstorms of varying intensity to occur at the edges of these domes. They don’t always have tornadoes,” he said.
Read the original article on Business Insider
