The National Weather Service has issued a flash flood watch for Vienna and Fairfax County beginning at noon Friday and lasting for much of the evening.
In Vienna, showers and thunderstorms could start before noon, with another chance of showers and thunderstorms between noon and 2 p.m., and again after 2 p.m. Highs will be near 86.
Several more showers are expected to happen in intervals throughout the evening and overnight hours, NWS says.
The weather service predicts rainfall could amount to an inch to 2 inches per hour in afternoon storms. That amount could cause local rivers, streams or creeks to overflow and flood surrounding low-lying areas, NWS says.
The watch ends at 11 p.m. Friday.
A chance of storms continues throughout the weekend, but will bring some heat relief: Temperatures in Vienna will hover around 76 on Saturday and 83 on Sunday.