Schedule: a typical Wednesday (the flights of Jul 29, 2026, re-dated). Real flights replace these once the FAA publishes them, usually about a day ahead.
SOUTHWEST · FLIGHT WN 3540
SCHEDULED · TYPICAL SCHEDULE
Wednesday, September 30 Today
WN 3540 · SAN → SJC
departs 4:15 PM PT · arrives 5:40 PM PT
Forecast issued Wed 3:00 PM ET · 4h before departure
Watch this flight
Other days
Today
Thu 10/1 37%
Fri 10/2 41%
Mon 10/5 29%
Tue 10/6 21%
Odds over time
Arrive at SJC more than 15 minutes late?
45%
chance · ±0 pts
+17 pts · 24h
HOW SURE WE ARE
High. The odds now come mostly from live FAA and airport data.
Arrive 15+ late
45%
Leave 15+ late
52%
Arrive 1h+ late
7%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
2.8d
2d
1d
12h
6h
Now
Departs
Lands
Arrive at SJC more than 15 minutes late?
Calm-weather odds: 25% · changed +17 pts in 24h
+17 pts
45%
Yes 45%
No 55%
Leave SAN more than 15 minutes late?
Calm-weather odds: 26% · changed +27 pts in 24h
+27 pts
52%
Yes 52%
No 48%
Arrive at SJC more than an hour late?
Calm-weather odds: 4% · changed +3 pts in 24h
+3 pts
7%
Yes 7%
No 93%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 100%
How late will it get to SJC?
On time or early
55%
15–30 min late
32%
30 min–1 hour late
5%
1–2 hours late
6%
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
↑
4pm departures from SAN are often late
↑
This flight has been late 42% of the time recently
↑
Later flights pick up delays from earlier in the day
↓
Wednesdays in September are usually quieter than average
↓
Mostly benign weather forecast at SJC
Weather at each end
SAN (origin)
Gusts 10 kt Ceiling 700 ft Visibility 8 mi Precip none
SJC (destination)
Gusts 13 kt Ceiling none (clear) Visibility 9 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.