Federal Agency Issues Heat Warnings to Millions

The National Weather Service's (NWS) map showing "excessive heat warnings" and heat advisories that are in effect across the United States on July 24, 2023. Weather.gov

National Weather Service (NWS) alerts for “excessive summer heat” across the United States were sent out on Monday, with the agency warning that more of the same is expected for the coming week.

The summer weather heat “will build and expand across the Eastern two-thirds of the country this week, starting in the north-central states and Plains,” the NWS said in a bulletin.

“A staunch upper level ridge will continue generating anomalous heat across parts of the West as well as southern Florida,” the NWS bulletin added.“ High temperatures in the 90s-110s and lows ranging from the upper 60s to 80s will likely tie or break records in many parts of the West,” it said, adding that low temperatures “as high as the 90s are possible for parts of the Southwest this week.

The agency currently has “excessive heat warnings” in effect for a range of counties across the southwestern U.S. states and in other parts of the West, including the Great Basin, Great Plains, and mountain regions.

Cities such as Salt Lake City, Phoenix, Oklahoma City, Dallas, and Billings will break 100 degrees on Monday, according to the agency’s forecast.

A heat advisory sign is shown along U.S. highway 190 during a heat wave in Death Valley National Park in Death Valley, California, on July 16, 2023. Ronda Churchill/AFP via Getty Images

Cities from Billings, Montana, through Salt Lake City, Phoenix, and Oklahoma City will break 100 degrees to start the workweek. Other cities, such as Denver and Kansas City, Missouri; Houston, Texas; and Omaha, Nebraska, will get very close to breaking 100 degrees during the day.

“As the record-breaking heat wave continues in the Southwest, by the latter part of the week, the heat will build eastward into the Midwest as well,” AccuWeather Senior Meteorologist Dan Pydynowski said.

Officials have said that the cyclic El Niño phenomenon that brings warmer water into the equatorial Pacific Ocean is causing higher-than-average global temperatures. This year’s El Niño started in June, while officials with the National Oceanic and Atmospheric Administration said the phenomenon will continue until March 2024.

“El Niño has become an intensely studied and widely publicized phenomenon which has been linked to changes in weather patterns across the United States. Often falsely blamed for crazy weather ranging from flooding and mudslides to snowstorms and tornadoes, in reality its effects are much broader and generalized and can never fully take credit for any one weather event. Its effects on one region may be drastically different than its effects on another region,” says the NWS on its website.