Updated Jun 26, 2023 - Science

Texas' record heat wave enters 3rd week as storms slam southern U.S.

 Dymond Black works on an electric fan while sitting in the shade on June 19, 2023 in Austin, Texas.

A camper with an electric fan sitting in the shade on June 19 in Austin, Texas, which has seen days of extremely high temperatures. Photo: Brandon Bell/Getty Images

Over 50 million people in the southern U.S. were under heat advisories and many others were facing the threat of severe weather that spawned tornadoes and thunderstorms over the weekend and into Monday.

State of play: The severe storms saw an estimated 168,000 customers lose power in Georgia, along with some 132,000 others in both Kentucky and Tennessee and a further 126,000 in Arkansas early Monday, while a series of suspected tornadoes late Sunday damaged property in Indiana and killed a person in the state's Martin County.

  • Thunderstorms caused flight delays in major transport hubs Sunday in New York City, Atlanta, Detroit, Cleveland, Louisville, Cincinatti, Philadelphia and Detroit, while flights to and from D.C.-area airports were suspended in the evening due to an air traffic control issue before the FAA switched to a "backup facility," per the Washington Post.
  • The National Weather Service warned as thunderstorms lashed Tennessee, Mississippi, Arkansas and parts of the Ohio Valley that "strong to severe storms" would move southward through Alabama and Georgia.

Meanwhile, in Texas, where the record-breaking heat wave entered a third week, the NWS office in San Angelo noted that a wind gust of 64 mph was recorded over the western community of Ozona during a "dry microburst" in a thunderstorm — which typically occurs with very little precipitation at the surface.

  • The NWS said the life-threatening "oppressive" heat dome was producing "dangerous heat and humidity in Texas and spread into the lower Mississippi River Valley," as new temperature records were set across the Lone Star State Sunday.
A screenshot of an NWS tweet saying: "We had some record heat today. San Angelo topped out at 112°, which smashed the previous record of 105° set back in 1994. It's hard to believe that just a week ago, 112° would've been our all-time record high and now it's just another day of 110° heat to add to the count #txwx NWS San Angelo @NWSSanAngelo · 3h Replying to  @NWSSanAngelo Abilene hit 106° which tied their previous record set all the way back in 1904°. That being said, with dew points in the 60's to near 70° all day, it certainly felt hotter. We didn't like our heat but we don't envy that humidity."
Photo: NWS San Angelo/Twitter

By the numbers: Del Rio hit a record high for June 25 of 110 degrees Fahrenheit Sunday — the eighth straight day that the city in southwestern Texas has seen a daily record high temperature set, according to the NWS.

  • Laredo in southern Texas has reached a record high temperature six days in a row and Sunday would likely be the seventh, per the NWS. "Four of those days have had a high above 110° including a tie of their all-time highest temp 115° on June 19," the weather service added.

Threat level: This searing heat wave in the south-central U.S. "shows no signs of letting up as a stagnant upper-level ridge remains in place," the weather services warned in an update early Monday.

  • "Widespread heat-related advisories are in effect for southern Arizona and New Mexico and across most of Texas as temperatures soar once again into the 100s" and some daily and overnight record-tying or record-breaking high temperatures were once again possible, the NWS said.

Context: Climate change is causing heat waves to be more intense, longer-lasting and more frequent, multiple studies show.

  • It's also leading to more intense extreme precipitation events due to a warmer atmosphere that can hold more water vapor — providing added moisture and energy to storm systems.
A screenshot of a tweet by NWS Houston, saying: "Heat Index Values at 5pm are generally between 105-115°F🥵  If you are planning on having any outdoor BBQs this evening be sure to drink plenty of water and take breaks in the shade or A/C to cool off."
Photo: NWS Houston/Twitter

Go deeper: Extreme heat in Texas and southern U.S. may linger until Fourth of July

Editor's note: This article has been updated to include new temperature records and more details from the storms.

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