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 3155
SCHEDULED · TYPICAL SCHEDULE
Wednesday, September 30 Tomorrow
WN 3155 · LAS → ONT
departs 2:25 PM PT · arrives 3:30 PM PT
Forecast issued Wed 12:00 AM ET · 17h before departure
Watch this flight
Other days
Today
Tue 10/6 17%
Odds over time
Arrive at ONT more than 15 minutes late?
33%
chance · ±1 pts
+11 pts · 24h
HOW SURE WE ARE
Good. The odds now lean mostly on firmed-up weather forecasts.
Arrive 15+ late
33%
Leave 15+ late
33%
Arrive 1h+ late
5%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
2.9d
2d
1d
Now
12h
6h
Departs
Lands
Arrive at ONT more than 15 minutes late?
Calm-weather odds: 25% · changed +11 pts in 24h
+11 pts
33%
Yes 33%
No 67%
Leave LAS more than 15 minutes late?
Calm-weather odds: 31% · changed +5 pts in 24h
+5 pts
33%
Yes 33%
No 67%
Arrive at ONT more than an hour late?
Calm-weather odds: 4% · changed +1 pt in 24h
+1 pt
5%
Yes 5%
No 95%
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
67%
15–30 min late
16%
30 min–1 hour late
11%
1–2 hours late
4%
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
↑
2pm departures from LAS are often late
↑
LAS is prone to delays
↑
LAS is busy at that time
↓
Wednesdays in September are usually quieter than average
↓
Mostly benign weather forecast at LAS
Weather at each end
LAS (origin)
Gusts 16 kt Ceiling 11,667 ft Visibility 10+ mi Precip none
ONT (destination)
Gusts 17 kt Ceiling none (clear) Visibility 8 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.