Schedule: the flights that flew on Tuesday, Sep 29, re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.

UNITED · FLIGHT UA 3891 SCHEDULED · TYPICAL SCHEDULE

Tuesday, October 6

UA 3891 · ACV → SFO

departs 7:59 AM PT · arrives 9:19 AM PT

Forecast issued Sun 7:00 AM ET · 52h before departure

Arrive at SFO more than 15 minutes late?

27% chance · ±2 pts – · 24h

HOW SURE WE ARE Moderate. The odds now blend history with early weather forecasts.

How late will it get to SFO?

On time or early
68%
15–30 min late
13%
30 min–1 hour late
3%
1–2 hours late
4%
Over 2 hours late
6%
Cancelled
7%

Gate arrival compared with the scheduled arrival. The ranges add up to 100%.

What’s moving the odds

↑ Cloud base down to 200 ft, visibility down to 0.3 mi forecast at ACV that day

↑ Arrivals into SFO at that hour are often late

↑ SFO is prone to delays

↓ Tuesdays in October are usually quieter than average

↓ Visibility down to 0.7 mi forecast at SFO that day

Weather at each end

ACV (origin) Gusts5 kt Ceiling200 ft Visibility0.4 mi Precipnone

SFO (destination) Gusts13 kt Ceilingnone (clear) Visibility0.8 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 3891 · ACV → SFO

Odds over time

How late will it get to SFO?