Schedule: a typical summer Sunday (the flights of Jul 26, 2026), re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.
SOUTHWEST · FLIGHT WN 3873
SCHEDULED · TYPICAL SCHEDULE
Sunday, October 4
WN 3873 · SNA → SMF
departs 9:10 PM PT · arrives 10:35 PM PT
Forecast issued Fri 10:00 PM ET · 50h before departure
Watch this flight
Other days
Today 60%
Sun 10/4
Mon 10/5 13%
Odds over time
Arrive at SMF more than 15 minutes late?
25%
chance · ±3 pts
−1 pt · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
25%
Leave 15+ late
31%
Arrive 1h+ late
6%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
10%
20%
30%
40%
6.1d
Now
1d
12h
6h
Departs
Lands
Arrive at SMF more than 15 minutes late?
Calm-weather odds: 25% · changed −1 pt in 24h
−1 pt
25%
Yes 25%
No 75%
Leave SNA more than 15 minutes late?
Calm-weather odds: 30% · changed +0 pts in 24h
+0 pts
31%
Yes 31%
No 69%
Arrive at SMF more than an hour late?
Calm-weather odds: 5% · changed +0 pts in 24h
+0 pts
6%
Yes 6%
No 94%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 99%
How late will it get to SMF?
On time or early
74%
15–30 min late
9%
30 min–1 hour late
10%
1–2 hours late
5%
Over 2 hours late
<1%
Cancelled
<1%
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
↑
WN's recent on-time record
↑
Sundays in October are usually busier than average
↓
Mostly benign weather forecast at SMF
↓
9pm departures from SNA are usually not late
Weather at each end
SNA (origin)
Gusts 14 kt Ceiling none (clear) Visibility 10+ mi Precip none
SMF (destination)
Gusts 7 kt Ceiling none (clear) Visibility 10+ mi Precip none
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.