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.

REPUBLIC · FLIGHT YX 4439 IN THE AIR (OFF 9:26 PM ET, ETA 10:34 PM ET) · SCHEDULED TIME UNKNOWN

Tuesday, September 29 Today

YX 4439 · BOS → BUF

took off 9:26 PM ET · expected to land 10:34 PM ET (scheduled time unknown)

Forecast issued Tue 8:00 PM ET · 2h before departure

Arrive at BUF more than 15 minutes late?

33% chance · ±1 pts +0 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

↑ 9pm departures from BOS are often late

↑ Later flights pick up delays from earlier in the day

↓ Tuesdays in September are usually quieter than average

↓ YX's recent on-time record

Weather at each end

BOS (origin) Gusts11 kt Ceiling600 ft Visibility1.5 mi Precip0.01 in

BUF (destination) Gusts6 kt Ceiling2,000 ft Visibility10+ mi Precip0.02 in

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.

YX 4439 · BOS → BUF

Odds over time