(NEW YORK) -- Half the country is bracing for what could be one of the worst storms of the tornado season. Concerns are growing in the South and Midwest with reports of tornadoes touching down in areas like North Carolina. Severe, isolated storms brought hail and damaging winds to the area, with hail falling in Durham and Fayetteville. Residents across Texas and Oklahoma have been prepping with severe weather safe rooms.
More than 200,000 were sold in the last year. Researchers at Texas Tech University found that the shelters can withstand wind speeds of up to 250 miles an hour.
Tornadoes are possible Saturday from Dallas to Des Moines, and later this weekend from Texas to St. Louis. The main threats are damaging wind, large hail, and the potential for large tornadoes, according to Russ Schneider, director of the Storm Prediction Center. Extreme conditions are expected through Tuesday.
In Virginia, fans at the Richmond International Raceway were forced out the stands by storms. Attendees at NASCAR's Sprint Cup qualifying session waited out the weather following delayed races.
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