Oklahoma remains under severe storm alert, Texas breaks heat records (Akhabar Factory)

Scattered severe storms continued across parts of Oklahoma on Saturday with the risk of possible tornadoes lasting into the night, as some parts of South Texas broke heat records and people were warned of triple-digit temperatures over the long holiday weekend.

Memorial Day is the unofficial start to summer, although the season does not officially start for another four weeks.

The National Weather Service’s office in Norman, Oklahoma, compared Saturday to “a gasoline-soaked brush pile”. Forecasters said any storms that form could explode with large hail, dangerous winds and tornadoes.

“There’s a small chance most of the matches are duds, and we only see a few storms today. Still, that’s not a match I would want to play with. It only takes one storm to be impactful,” the office said via Facebook.

Excessive heat, especially for May, is the danger in South Texas, where the heat index was forecast to approach 49 degrees Celsius in some spots during the weekend. Actual temperatures will be lower, although still in triple-digit territory, but the humidity will make it feel that much hotter.

The region is on the north end of a heat dome that stretches from Mexico to South America, National Weather Service meteorologist Zack Taylor said.

Sunday looks like the hottest day with record highs for late May forecast for Austin, Brownsville, Dallas and San Antonio, Taylor said.

Brownsville and Harlingen near the Texas-Mexico border already set new records Saturday for the May 25 calendar date — 37 degrees Celsius and 38 degrees Celsiu), respectively, according to the weather service.

Red Flag fire warnings were also in place in West Texas, all of New Mexico and parts of Oklahoma, Arizona and Colorado. Humidity was very low, under 10 per cent, and wind gusts of up to 60 mph (97 kph) were recorded.

“We’ve got very dry air, warm temperatures and strong winds creating a high fire danger over a wide area that can lead to rapidly spreading or uncontrollable fires,” Taylor said.

Meanwhile, several inches of snow fell Friday into early Saturday in Rolla, North Dakota, about 16 km from the Canadian border.

April and May have been a busy month for tornadoes, especially in the Midwest. Climate change is heightening the severity of storms around the world.

April saw the US’ second-highest number of tornadoes on record. So far for 2024, the country is already 25 per cent ahead of the average number of twisters, according to the Storm Prediction Center in Norman.

Iowa was hit hard this week, when a deadly twister devastated Greenfield. And other storms brought flooding and wind damage elsewhere in the state.

The storm system causing the severe weather was expected to move east as the Memorial Day weekend continues, bringing rain that could delay the Indianapolis 500 auto race Sunday in Indiana and more severe storms in Illinois, Indiana, Missouri and Kentucky.

The risk of severe weather moves into North Carolina and Virginia on Monday, forecasters said.