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 4984
SCHEDULED · TYPICAL SCHEDULE
Sunday, October 4
WN 4984 · SMF → ONT
departs 9:40 PM PT · arrives 11:00 PM PT
Forecast issued Fri 9:00 PM ET · 52h before departure
Watch this flight
Other days
Today 23%
Sun 10/4
Mon 10/5 22%
Odds over time
Arrive at ONT more than 15 minutes late?
31%
chance · ±2 pts
+0 pts · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
31%
Leave 15+ late
35%
Arrive 1h+ late
10%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
6.1d
Now
1d
12h
6h
Departs
Lands
Arrive at ONT more than 15 minutes late?
Calm-weather odds: 30% · changed +0 pts in 24h
+0 pts
31%
Yes 31%
No 69%
Leave SMF more than 15 minutes late?
Calm-weather odds: 40% · changed −2 pts in 24h
−2 pts
35%
Yes 35%
No 65%
Arrive at ONT more than an hour late?
Calm-weather odds: 9% · changed +0 pts in 24h
+0 pts
10%
Yes 10%
No 90%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 100%
How late will it get to ONT?
On time or early
68%
15–30 min late
9%
30 min–1 hour late
12%
1–2 hours late
7%
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
↑
Later flights pick up delays from earlier in the day
↑
WN's recent on-time record
↑
Arrivals into ONT at that hour are often late
↓
Mostly benign weather forecast at SMF
↓
Mostly benign weather forecast at ONT
Weather at each end
SMF (origin)
Gusts 7 kt Ceiling none (clear) Visibility 10+ mi Precip none
ONT (destination)
Gusts 16 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.