The National Weather Service has issued a flash flood warning Wednesday for Allegheny County, Washington County and Westmoreland County.
The warning is in effect until 7:15 p.m., and comes as a severe thunderstorm warning was issued for Allegheny and Westmoreland counties. That thunderstorm warning expired, but another was issued for Westmoreland and Fayette counties that ended at 5:45 p.m.
Severe Weather Team 11 meteorologist Stephen Cropper said the slow-moving storms have the potential for heavy rain, damaging winds and hail in some areas.
Flooding is possible in small streams and low-lying areas and roadways.
Flooding and power outages have been reported in McKeesport, Elizabeth and Versailles, and lightning reportedly sparked a house fire in Penn Hills.
Officials in Elizabeth said several people have been rescued from vehicles after becoming trapped by floodwaters.
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