US: Flash flood warning in effect for Allegheny County, Pa., through at least 21:30 June 26

The US National Weather Service (NWS) has issued a flash flood warning for Allegheny County, Pennsylvania, until at least 21:30 June 26. Areas under flash flood warnings include the cities of Pittsburgh, Bethel Park, and Monroeville. Officials could update or amend the warning for the impact areas or surrounding region in the coming hours.

Sustained heavy rainfall could trigger flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly or mountainous areas, especially where the soil has become saturated by heavy rainfall.

Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.