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 588
SCHEDULED · TYPICAL SCHEDULE
Wednesday, September 30 Yesterday
WN 588 · SMF → ONT
departs 6:50 PM PT · arrives 8:15 PM PT
Forecast issued Wed 10:00 PM ET · 0h before departure
Watch this flight
Other days
Wed 9/30
Tue 10/6 16%
Wed 10/7 16%
Odds over time
Arrive at ONT more than 15 minutes late?
19%
chance · ±0 pts
−1 pt · 24h
HOW SURE WE ARE
Very high. The odds now come almost entirely from live conditions.
Arrive 15+ late
19%
Leave 15+ late
27%
Arrive 1h+ late
4%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
10%
20%
30%
40%
2.8d
2d
1d
12h
6h
Departs
Lands
Arrive at ONT more than 15 minutes late?
Calm-weather odds: 19% · changed −1 pt in 24h
−1 pt
19%
Yes 19%
No 81%
Leave SMF more than 15 minutes late?
Calm-weather odds: 28% · changed −1 pt in 24h
−1 pt
27%
Yes 27%
No 73%
Arrive at ONT more than an hour late?
Calm-weather odds: 4% · changed +0 pts in 24h
+0 pts
4%
Yes 4%
No 96%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 99%
How late will it get to ONT?
On time or early
81%
15–30 min late
8%
30 min–1 hour late
7%
1–2 hours late
2%
Over 2 hours late
2%
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
↑
6pm departures from SMF are often late
↓
Wednesdays in September are usually quieter than average
↓
Mostly benign weather forecast at SMF
Weather at each end
SMF (origin)
Gusts 6 kt Ceiling none (clear) Visibility 10+ mi Precip none
ONT (destination)
Gusts 18 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.