Watch Issued for Severe Thunderstorm

The National Weather Service issued a severe thunderstorm watch for several counties in western Pennsylvania.

The watch is in effect until 10 p.m. for Allegheny, Butler, Beaver, Greene, Lawrence, Mercer, Venango and Washington counties.

The weather service issues a severe thunderstorm watch when conditions are favorable for severe thunderstorms to develop, according to the NWS website.

"A severe thunderstorm by definition is a thunderstorm that produces one inch hail or larger in diameter and/or winds equal or exceed 58 miles an hour," the website states.

Keeping up with news in the Sewickley Patch is easy—simply like us on Facebook, follow on Twitter or get the Patch newsletter.