Strong storms hit downtown San Antonio this morning just in time to cancel the HEB Alamo Run Fest.

"Kind of bummed but I understand it's in the best interest of all of us," Participant Aubrey said.

Sunday was her mother Denise's 50th birthday. They looked forward to the run.

"A lot of people worked really hard to come out and do that, and it's kind of disappointing when maybe you were doing your first 5K and you are not able to hit those goals," Jake Porter, a trainer with Camp Gladiator, said.

Before leaving the Alamodome right before the storms hit, people made the most of it with an indoor workout.

"We decided to put everybody through a workout. Wanted to make sure that people were still going to get that burn and still be able to burn some calories," Porter said

Following the storm, CPS Energy crews were kept busy restoring power to thousands.

CPS Energy spokesperson Albert Cantu said, "This storm when it came into the city near about 8 o'clock we started to see some of those outages starting to happen."

When customers lose power because of thunderstorms CPS energy has to travel an entire circuit to figure out if it was a wire or a transformer that knocked out power.

But with all the lightning, crews had to wait until a blue sky returned to administer repairs.

"To be up on those poles trying to fix power or to put primary lines back up our guys are going to have to hold off until the lightning slows down," Cantu said.