Fun in the sun this weekend will hit a little bump in the early evening Saturday.

According to WTAE meteorologist Jill Szwed, some scattered thunderstorms heading for the Pittsburgh and Greensburg areas are predicted to turn severe.

“The likely onset for Pittsburgh and Greensburg will be between 5 and 7 p.m.,” Szwed said in an email. “Damaging winds are the primary threat along with flash flooding rain – heavy rain over a short period of time.”

The threat of large hail and a tornado is lower, she said.

According to a post from National Weather service, an isolated tornado can’t be ruled out as of Saturday morning.

“If a storm were to spin off a tornado, it is more likely earlier this afternoon before a line of storms forms. The line will channel straight-line winds,” Szwed said.

Storms are expected to hit Western Pennsylvania by 2 p.m. NWS warned people to keep an eye on forecasts and possible alerts as the storms develop into the evening.

Storms are predicted to fizzle out before sunset as they head south.