Mild and humid conditions are expected overnight as a cold front approaches from the west. As the atmosphere becomes more unstable, showers and thunderstorms will develop.

Labor Day will be filled with clouds and highs near 80 degrees. Showers and thunderstorms will arrive late afternoon and into the early evening hours. Some storms will contain frequent lightning and periods of heavy rain. If planning outdoor activities for the holiday, be sure to have an alternate sheltered plan. The cold front will stall south of the District on Tuesday allowing for the remnants of "Lee" to move overhead. The latest models indicate the heaviest of the rain will fall west of D.C. Flash flooding will be possible, especially across the Shenandoah Valley. Rain totals may exceed three-inches.

"Katia" continues to spin in the Atlantic, track the latest here. Stay with ABC7, News Channel 8, WJLA.com and Weather Now for additional updates.