The National Weather Service has issued a severe thunderstorm watch for the entire Delaware Valley including Bucks and Montgomery counties.

The watch is in effect until 10 p.m.

Be on the lookout for a local upgrade to a thunderstorm warning.

Here's the local forecast:

• This Afternoon: Showers and thunderstorms, mainly after 4pm. Some storms could be severe, with damaging winds, heavy rain, and frequent lightning. High near 86. Breezy, with a southwest wind around 21 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
• Tonight: Showers and thunderstorms before 11pm, then showers likely and possibly a thunderstorm between 11pm and 1am, then a chance of showers and thunderstorms after 1am. Some storms could be severe, with damaging winds, gusty winds, heavy rain, and frequent lightning. Low around 63. Southwest wind 6 to 14 mph becoming northwest after midnight. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
• Sunday: Mostly sunny, with a high near 78. Northwest wind 7 to 11 mph.
• Sunday Night: Partly cloudy, with a low around 56. North wind 5 to 7 mph.