Tornadoes touch down in Arkansas and Oklahoma

Warmer weather contributed to tornadoes in Arkansas and Oklahoma Wednesday evening, including one that raked Tulsa and its suburbs during the evening rush hour.

The slow start to the nation's tornado season came to a blustery end Wednesday when tornadoes hit Arkansas and Oklahoma, including one that raked Tulsa and its suburbs during the evening rush hour.

Emergency managers reported no injuries when a late-afternoon storm hit Sand Springs, Oklahoma, and raced eastward into Tulsa. Until Tuesday, when a waterspout formed over an Arkansas lake, the U.S. hadn't had a tornado in more than a month.

Sirens also went off at Moore, Oklahoma, where 24 people died in a top-of-the-scale EF5 tornado in 2013. Television coverage Wednesday evening showed a small twister on the ground. Another tornado was reported near the fairgrounds in western Oklahoma City.

The tornado season usually ramps up for parts of the U.S. in March, but weather patterns funneled cold air into much of the country, depriving the atmosphere of the warm, moist air necessary for form bad storms for most of the month.

That all changed this week. Southerly winds pushed temperatures into the 70s and 80s across the Ozarks and Southern Plains, while weather fronts churned the air into Wednesday's storms.

Meteorologist Jeff Hood in Little Rock said a weak "waterspout" tornado briefly touched down in Bull Shoals Lake in Marion County in northwest Arkansas on Tuesday night. He said it will likely be classified an EF0 — the weakest tornado with wind speeds of 65 to 85 mph. A "waterspout" forms over water. The tornado Tuesday never made it onto land, and there were no reports of damage.

"This will be the 'tornado' that breaks the drought for March," Greg Carbin, warning coordination meteorologist for the Storm Prediction Center, said Wednesday.

Before this week, only about two-dozen twisters had been recorded this year during a period when about 120 are typical. The last time the U.S. had no twisters in March was nearly 50 years ago, according to figures from the Storm Prediction Center in Norman, Oklahoma.

Associated Press reporters Ken Miller, Sean Murphy and Tim Talley contributed to this report from Oklahoma City.