As extreme temperatures continue to plague the nation, at least 12 people have passed away in Texas and Louisiana from heat-related causes.
According to local authorities, 11 of the fatalities occurred in Webb County, Texas, near the border with Mexico.
Breaking previous records, emergency rooms in Texas have received hundreds more patients.
The result of a heat dome, which occurs when high pressure is trapped due to wind patterns, is the current weather.
The fatalities from heat stroke ranged in age from 60 to 80 in Webb Country, which is centered on the city of Laredo.
County medical examiner Dr. Corinne Stern stated, "We don't see this in our county," during a meeting of local officials on Tuesday.
"Laredo is a heat expert. Webb County is used to heat. And I believe that our county was somewhat unprepared.
"Due to this dome of high pressure, these temperatures are unprecedented here. " .
A man and his stepson, 14, who were hiking in Texas' Big Bend National Park, were also among the deceased.
According to data from the Centers for Disease Control and Prevention (CDC), between June 18 and 24, Texas experienced an average of 837 heat-related visits per 100,000 visitors, up from 639 during the same time period in 2017.
According to CBS, the BBC's US partner, two more people died in Caddo Parish, Louisiana, as a result of the heat, including a 49-year-old man and a 62-year-old woman.
The New Mexico desert's busy corridor for human smuggling also contained five bodies that were discovered there. If those deaths were directly related to the heat, officials have not said so.
A relatively uncommon "heat dome," which only happens occasionally in the southern US, is the cause of the current heat wave. A heat dome occurs when high pressure is trapped in a specific location due to wind patterns, extending 5 to 10 miles (8 to 16 km) in altitude and hundreds of thousands of miles horizontally.
In particular in the southern US and the Mississippi Valley, meteorologists anticipate that the heat wave will continue to spread over the ensuing days.
There are still heat advisories in effect for large portions of Texas, Louisiana, Arkansas, Alabama, Kansas, and other states. For the remainder of the week, New Mexico, Georgia, and Florida are also expected to experience temperatures that are above average.
The National Weather Service and federal health authorities have issued warnings due to the heat, advising residents of the affected areas to limit their time spent outdoors and spend as much time as possible indoors where it is air conditioned.
According to CDC statistics, there are approximately 702 heat-related deaths and nearly 68,000 visits to emergency rooms each year in the US.
According to scientists, human-induced climate change has caused heatwaves to intensify and last longer.
Scientists predict that temperatures will continue to rise unless governments around the world implement drastic emission reduction measures. The world has already warmed by about 1 point 1C since the start of the industrial era.