PITTSBURGH (KDKA) — Tens of thousands of people are without power after storms hit Western Pennsylvania amid a heat wave on Monday. 

Severe weather rolled through the area on Monday evening, as many people saw severe thunderstorm warnings in their cities. All previous severe-thunderstorm-related watches and warnings have since expired. 

Duquesne Light said more than 47,000 customers in Western Pennsylvania are without power as of 7:10 p.m. on Monday. Brighton, Hampton, Monroeville, Moon, Richland and Shaler are among the municipalities that have more than 1,000 customers without power. 

West Penn Power said more than 27,000 customers are without power as of 7:04 p.m. on Monday. Allegheny, Armstrong, Beaver, Butler and Westmoreland counties all have more than 1,000 customers without power, including more than 9,000 customers in Allegheny and Westmoreland counties. 

The Pittsburgh area is under an excessive heat watch that lasts through the end of the week. A heat wave is a stretch of three or more days in a row with temperatures in the high 90s with no point during the stretch falling below 70 degrees Fahrenheit. 

Western Pennsylvania has not seen this type of heat wave since 1988, and the National Weather Service has only issued three excessive heat watches since 2011. 

Several cooling centers are open to help people catch a break from the heat.