Schedule: the flights that flew on Sunday, Oct 25, re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.
SOUTHWEST · FLIGHT WN 4020
SCHEDULED · TYPICAL SCHEDULE
Sunday, November 1
WN 4020 · ONT → SJC
departs 3:51 PM PT · arrives 5:17 PM PT
Forecast issued Sat 1:00 AM ET · 43h before departure
Watch this flight
Odds over time
Arrive at SJC more than 15 minutes late?
29%
chance · ±3 pts
−1 pt · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
29%
Leave 15+ late
43%
Arrive 1h+ late
10%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
10%
20%
30%
40%
6.8d
Now
1d
12h
6h
Departs
Lands
Arrive at SJC more than 15 minutes late?
Calm-weather odds: 30% · changed −1 pt in 24h
−1 pt
29%
Yes 29%
No 71%
Leave ONT more than 15 minutes late?
Calm-weather odds: 35% · changed −2 pts in 24h
−2 pts
43%
Yes 43%
No 57%
Arrive at SJC more than an hour late?
Calm-weather odds: 6% · changed −1 pt in 24h
−1 pt
10%
Yes 10%
No 90%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 99%
How late will it get to SJC?
On time or early
71%
15–30 min late
11%
30 min–1 hour late
8%
1–2 hours late
8%
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
↑
WN's recent on-time record
↑
Later flights pick up delays from earlier in the day
↑
SJC is prone to delays
↓
ONT usually runs smoothly
↓
Mostly benign weather forecast at SJC
Weather at each end
ONT (origin)
Gusts 16 kt Ceiling 1,300 ft Visibility 4 mi Precip 0.30 in
SJC (destination)
Gusts 14 kt Ceiling 6,000 ft 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.