After an afternoon filled with tornado sirens, lightning strikes, torrential rain and visible cloud rotation near Iowa Speedway, IndyCar canceled Friday afternoon practice.

A tornado warning for southeastern Guthrie County was allowed to expire as planned for 12:15 a.m. Friday. According to the National Weather Service, a severe thunderstorm capable of producing a tornado was located near Casey at 11:45 p.m., moving east at 35 mph.

Due to the storm's huge hail, severe gusts, and frequent cloud-to-ground lightning, the weather service urges people to seek refuge in an inside room on the lowest floor of a building for their own sa

Having reliable, loud, and timely emergency alerts on your phone or device is important because when severe weather strikes, every second counts.

The tornado warnings in Atlantic and Ocean counties in New Jersey are no longer in effect on Wednesday night. Earlier Wednesday, a tornado warning in New Castle County, Delaware, expired at around 9:15 p.m. A severe thunderstorm watch was in effect across much of the Philadelphia region for Wednesday evening.

Intense warnings issued in D.C. and surrounding counties threaten power and safety. Stay informed with the latest updates.

The National Weather Service released a severe thunderstorm warning at 3:09 p.m. on Wednesday in effect until 4:15 p.m. for Colbert, Franklin, Lauderdale and Lawrence counties.

A "considerable" flash flood warning has been issued in Boston as heavy, life-threatening rain pounds the city and areas to the south. Two to 4 inches of rain has fallen so far. Rainfall rates are reaching up to 2 inches per hour.