OKLAHOMA CITY (AP) — At least two tornadoes touched down in Oklahoma and another hit Arkansas on Thursday as a powerful storm system moved through the middle of the country. At least one injury was reported when a home was hit in rural western Arkansas. The National Weather Service reported two tornadoes on the ground near Perkins and Ripley in north central Oklahoma and another west of Oden, Ark. Arkansas Emergency Management spokesman Tommy Jackson said first responders were having trouble reaching the destroyed home because a number of trees were blocking the road. Montgomery County Sheriff's spokeswoman Brandy Wingfield said there was property damage, including downed power lines, in the area. Perkins Emergency Management Director Travis Majors said there were no injuries or damage there. Ripley, about 10 miles east of Perkins, did not seem to have significant damage. The Payne County emergency management director did not immediately return a phone call seeking comment. Thursday's tornadoes were much less dangerous than the EF5 storm that struck Moore, Okla., on May 20 and killed 24 along its 17-mile path. The U.S. averages more than 1,200 tornadoes a year, but top-of-the-scale storms like the one in Moore — with winds over 200 mph — happen only about once per year. The tornado last week was the nation's first EF5 since 2011. This spring's tornado season got a late start, with unusually cool weather keeping funnel clouds at bay until mid-May. The season usually starts in March and then ramps up for the next couple of months. The Storm Prediction Center in Norman, Okla., warned that there was a moderate risk of severe weather Thursday over much of eastern and central Oklahoma, with storms also possible in the rest of the central United States from Texas to Wisconsin. In addition to tornadoes, the storms were bringing rain and hail. "Right now we've been getting a few thunderstorms, but they're very severe supercell thunderstorms," said Michael Scotten, a meteorologist with the National Weather Services. "The whole storm rotates, and they produce on occasion some tornadoes and heavy hail." The severe weather threat led organizers to postpone the start of the outdoor Wakarusa Music Festival near Ozark, Ark., which will feature Widespread Panic, The Black Crowes and the rapper Snoop Lion (formerly known as Snoop Dogg). An estimated 15,000 sought shelter from lightning and wind Thursday, according to the Times Record newspaper of Fort Smith, Ark. Of the 60 EF5 tornadoes since 1950, Oklahoma and Alabama have been struck the most, seven times each. More than half of these top-of-the-scale twisters have occurred in just five states: Alabama, Iowa, Kansas, Oklahoma and Texas. Fewer than 1 percent of all U.S. tornadoes are this violent — only about 10 a year, according to research meteorologist Harold Brooks at the National Severe Storms Laboratory in Norman.