Since our metrorail system lacks flexibility (read: express-local track configuration) to do ongoing track improvements, three-day weekends are often used by WMATA to fix, upgrade or rebuild sections of rail lines. And the upcoming three-day President’s Day weekend is no different. And weekend commuting could be slow as molasses if you’re passing through or going to or from Alexandria.

According to WMATA, improvements to the King Street metrorail station in Alexandria will necessatate single tracking between the Braddock Road station on the Blue and Yellow lines and the Huntington terminal station on the Yellow Line and Van Dorn Street on the Blue Line. This will start after 10 p.m. on Friday and end at the end of service on Monday.

This weekend’s work won’t be the end of single-tracking in Alexandria. WMATA says stay tuned for more King Street-related sluggishness.