Schedule: a typical summer Friday (the flights of Jul 31, 2026), re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.

DELTA · FLIGHT DL 509 SCHEDULED · TYPICAL SCHEDULE

Friday, October 2 Yesterday

DL 509 · DTW → SFO

departs 6:55 PM ET · arrives 8:55 PM PT

Forecast issued Fri 10:00 PM ET · 3h after departure

Arrive at SFO more than 15 minutes late?

25% chance · ±1 pts −1 pt · 24h

HOW SURE WE ARE Very high. The odds now come almost entirely from live conditions.

How late will it get to SFO?

On time or early
75%
15–30 min late
6%
30 min–1 hour late
9%
1–2 hours late
7%
Over 2 hours late
3%
Cancelled
<1%

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

What’s moving the odds

↑ This flight has been late 41% of the time recently

↑ Arrivals into SFO at that hour are often late

↑ Later flights pick up delays from earlier in the day

↓ Cloud base down to 300 ft forecast at SFO that day

↓ DTW usually runs smoothly

Weather at each end

DTW (origin) Gusts28 kt Ceiling800 ft Visibility1.75 mi Precip1.43 in

SFO (destination) Gusts10 kt Ceiling300 ft Visibility3 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.

DL 509 · DTW → SFO

Odds over time

How late will it get to SFO?