US Severe weather: Extreme heat in Southwest, Gulf rain and Rockies snow

PHOENIX (AP) — Heat and cold extremes are expected this week in the U.S. Officials warned Southwest residents to take precautions as a heat wave moves east, while heavy rains and flooding could drench the Gulf states and snow threatens parts of the Rockies and Northwest.

Extreme heat spread across Arizona, New Mexico and parts of Texas, Colorado and Kansas as severe weather swept across many parts of the U.S. on Sunday. There was unseasonable cold in the Pacific Northwest, snow headed to the northern Rocky Mountains and heavy rainfall forecast from the northern Plains to the Upper Midwest.

The National Weather Service estimated more than 63 million people were under heat advisories on Sunday, stretching from the Southwest northward up through Denver and into Chicago.

Temperatures in Phoenix, which hit 112 degrees Fahrenheit (44.4 Celsius) on Saturday, eased slightly on Sunday to 110 degrees Fahrenheit (43.3 Celsius). Weather service forecasters say the first two weeks of June in Phoenix already have been an average of 5.6 degrees Fahrenheit hotter than normal, making it the hottest start to June on record.

“We have already seen some pretty significantly high temperatures in our area,” said Ted Whittock, a meteorologist with the National Weather Service in Phoenix. “We are recommending that everyone reduce their time outdoors between 10 a.m. and 6 p.m., stay hydrated and wear light, looser fitting clothing.”

The heat in metro Phoenix will ease a bit Monday through Wednesday, with the highs pushing back up as the week progresses, likely prompting another excessive heat warning, Whittock said.

The heat has been especially dangerous in recent years in metro Phoenix, where 645 people died from heat-related causes in 2023, which was a record.

The city and Maricopa County have adopted additional measures this year in hopes of keeping people safer, including two new overnight cooling centers where people can rest in air conditioning after the sun goes down. There are more than 100 other cooling centers that have been open since May 1 where people can get cold water and sit in a cool space during daytime hours.

In neighboring New Mexico, a heat advisory was in effect