Highs near Vienna will plummet from the low 80s on Friday, Oct. 16, to the mid-50s by Saturday as a cold front sweeps through Northern Virginia. The shift brings the season's first frost risk to communities west of Interstate 95, including Vienna and Oakton.

The National Weather Service (NWS) expects scattered thunderstorms Friday afternoon and evening, with the greatest severe-storm potential east of the Blue Ridge Mountains. Wind gusts of 35 to 45 mph are possible Friday into Saturday, strong enough to knock down tree limbs and cause isolated power outages, Megan VerHelst of Patch reported, citing the weather service.

AccuWeather said the strongest thunderstorms across the broader Mid-Atlantic could generate winds of 55 to 65 mph, though those speeds are not expected everywhere.

Saturday's drop

The NWS forecasts Saturday highs of 54 to 55 degrees in the Arlington, Alexandria and Falls Church area. That is a drop of more than 25 degrees from Friday's expected high near 82.

Wind will make it feel worse. AccuWeather predicted Saturday morning could feel like the 30s or lower 40s along the I-95 corridor.

Sunday highs stay in the mid-to-upper 50s.

Frost risk hits Vienna's side of I-95

The coldest stretch arrives late Saturday night into Sunday morning, when temperatures could dip into the 30s across much of Northern Virginia. The NWS said frost is possible in communities west of I-95, a zone that includes Vienna, Oakton and much of western Fairfax County.

Farther east, Arlington and Alexandria are expected to stay closer to 40 degrees overnight, making a freeze less likely there.

Residents with sensitive outdoor plants should bring them inside or cover them Saturday evening, particularly in western Fairfax, Loudoun and Prince William counties. Saturday's chill means jackets for anyone at a pumpkin patch or fall festival.

When it warms up

The cold snap should be short-lived. The NWS forecasts highs in the lower 60s Monday, Oct. 19, and mid-60s Tuesday, Oct. 20, around the region.

Weekend forecast at a glance

  • Friday, Oct. 16: High near 82. A chance of thunderstorms after 5 p.m. South wind 11-13 mph, gusts to 24 mph.
  • Friday night: Showers and thunderstorms likely. Low around 50. Northwest wind around 14 mph, gusts to 24 mph.
  • Saturday, Oct. 17: High near 54. Mostly sunny after early showers. North wind 16-18 mph, gusts to 30 mph.
  • Saturday night: Mostly clear. Low around 37. Frost possible west of I-95.
  • Sunday, Oct. 18: Sunny. High near 56.

This weekend in Vienna

  • Saturday, Oct. 17: Fall Festival at Wesley UMC, 711 Spring St. SE. Dress warmly.