Tracked live by the FAA, but its flight plan was first seen after takeoff, so we don't know the scheduled time and can't say whether it's late.

UNITED · FLIGHT UA 755 LANDED 8:56 PM ET, ~13 MIN LATE · SCHEDULED TIME UNKNOWN
Yesterday

UA 755 · SFO → IAD

took off 1:21 PM PT · landed 8:56 PM ET (scheduled time unknown)
Forecast issued Mon 10:00 PM ET · 6h after departure

Odds over time

Arrive at IAD more than 15 minutes late?
30% chance · ±0 pts +9 pts · 24h
HOW SURE WE ARE Very high. The odds now come almost entirely from live conditions.
WEATHER FORECASTS LIVE IN THE AIR 0% 10% 20% 30% 40% 1.1d 12h 6h Departs Lands