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.

DELTA · FLIGHT DL 21 SCHEDULED · TYPICAL SCHEDULE

Tuesday, October 6

DL 21 · LHR → SEA

departs 5:36 PM BST · arrives 7:19 PM PT

Forecast issued Sun 4:00 AM ET · 57h before departure

Arrive at SEA more than 15 minutes late?

11% chance · ±0 pts – · 24h

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

How late will it get to SEA?

On time or early
86%
15–30 min late
3%
30 min–1 hour late
4%
1–2 hours late
2%
Over 2 hours late
2%
Cancelled
3%

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

What’s moving the odds

↑ Later flights pick up delays from earlier in the day

↑ Arrivals into SEA at that hour are often late

↑ Mostly benign weather forecast at LHR

↓ Other factors

↓ Tuesdays in October are usually quieter than average

Weather at each end

LHR (origin) Gusts— Ceiling— Visibility— Precip—

SEA (destination) Gusts10 kt Ceiling300 ft Visibility9 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 21 · LHR → SEA

Odds over time

How late will it get to SEA?