Flood Watch in Effect

Torrential rain produced by severe storms could lead to flash flooding in the Lehigh Valley and other parts of southeastern Pennsylvania Wednesday evening, according to forecasters.

The National Weather Service has issued a flood watch that includes Northampton, Lehigh and Bucks counties from 5 p.m. Wednesday to 2 a.m. Thursday, when showers and thunderstorms could produce locally heavy rainfall at rates of 2 to 3 inches per hour.

According to a NWS statement, “with an already saturated surface, it will not take much rainfall to result in flooding.”

Meteorologists with the NWS said the greatest risk for widespread flash flooding Wednesday will be south of the Lehigh Valley in an area that includes Philadelphia, Delaware County, southern Chester and Lancaster counties and northern Delaware.

The moderate risk of flash flooding there means that many streams could flood, potentially affecting larger rivers.

Residents throughout the region are being advised to monitor radar for the development of storms and stay tuned to local weather forecasts, particularly if they live in flood-prone areas.

Due to atmospheric instability and tropical moisture that is already in place, the threat of heavy rain is expected to continue through the end of the week, along with generally hot, humid conditions.

According to the latest forecast for the Allentown area, there is a 30 to 40 percent chance of showers and thunderstorms Thursday and up to a 50 percent chance of thunderstorms and showers after 2 p.m. Friday. Highs will be in the mid to upper 80s.

Hellertown’s Dewey Fire Co. is holding its annual carnival this week, with a fireworks show scheduled for Friday evening. Tuesday night’s carnival was canceled due to rain, and wet weather on Friday night could postpone the fireworks to Saturday.

On the carnival Facebook page, organizers posted that Tuesday’s First Responder night will now be held Thursday.

Wednesday’s carnival will feature a car show.