The first real threat of tornadoes for the Tulsa area is on Sunday.
National Weather Service out of Tulsa says there is a slight change of showers and thunderstorms before 8 a.m. and after 4 p.m. on Sunday. Some of those storms could become severe.
A possible chance of tornadoes comes into play Sunday evening.
"They're going to go severe pretty quickly," National Weather Service says. "Very large hail. Damaging winds. A tornado threat can be expected with those storms."
Monday has a 50 percent chance of showers and thunderstorms. National Weather Service says the rain should start by the afternoon.
"The environment is going to be very similar (to Monday), very unstable," National Weather Service says. "Lots of wind sheer which helps these storms become very intense and organized. So we're looking at high-end severe weather for Sunday and Monday."
4:30 a.m. update: PSO says 573 customers are without power in the Tulsa area.
3 a.m. update: Organizers say 30 percent of the Blue Dome Festival tents were damaged or destroyed by strong wind gusts during the overnight storm. Nobody was hurt.
1:20 a.m. update: Power lines go down because of strong winds on Sheridan. This caused North and Southbound lanes to be closed from 11th to 15th. PSO says over 1,500 customers are without power.
12:45 a.m. update: Severe storms cause power outages and people to be evacuated from a mall in Oklahoma City Saturday evening.
OG&E says over 13,000 customers were without power in the OKC area.
Police say Quail Springs Mall had to be evacuated because of the outages and a few people had to be evacuated from an elevator inside the mall after the power went out.
No reports of any serious injuries.