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 421 IN THE AIR (OFF 11:08 PM ET, ETA 11:34 PM CT) · SCHEDULED TIME UNKNOWN

Tuesday, September 29 Yesterday

UA 421 · IAD → ORD

took off 11:08 PM ET · expected to land 11:34 PM CT (scheduled time unknown)

Forecast issued Tue 10:00 PM ET · 1h before departure

Arrive at ORD more than 15 minutes late?

28% chance · ±0 pts +9 pts · 24h

HOW SURE WE ARE High. The odds now come mostly from live FAA and airport data.

What’s moving the odds

↑ Other factors

↑ Arrivals into ORD at that hour are often late

↑ Cloud base down to 100 ft, visibility down to 0.5 mi forecast at ORD that day

↓ Tuesdays in September are usually quieter than average

↓ Mostly benign weather forecast at IAD

Weather at each end

IAD (origin) Gusts9 kt Ceiling4,200 ft Visibility8.8 mi Precipnone

ORD (destination) Gusts16 kt Ceiling100 ft Visibility0.5 mi Precipnone

How this resolves

Yes if the gate arrival is more than 15 minutes after the scheduled arrival. Cancelled or diverted flights resolve N/A.

Every question here is display only — there is no betting or money involved. Gate times come from the airline; a cancellation resolves only the “Cancelled?” question, and a diversion voids the delay questions.

UA 421 · IAD → ORD

Odds over time