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 304 LANDED 10:34 PM ET, ~6 MIN LATE · SCHEDULED TIME UNKNOWN

UA 304 · ORD → IAD

took off 8:15 PM CT · landed 10:34 PM ET (scheduled time unknown)
Forecast issued Tue 10:00 PM ET · 1h 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