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 4151
SCHEDULED · TYPICAL SCHEDULE
Sunday, October 4 Tomorrow
WN 4151 · SAN → DEN
departs 4:50 PM PT · arrives 8:15 PM MT
Forecast issued Sat 3:00 PM ET · 29h before departure
Watch this flight
Other days
Sun 10/4
Mon 10/5 26%
Fri 10/9 34%
Odds over time
Arrive at DEN more than 15 minutes late?
41%
chance · ±0 pts
+0 pts · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
41%
Leave 15+ late
52%
Arrive 1h+ late
10%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
5.9d
2d
Now
1d
12h
6h
Departs
Lands
Arrive at DEN more than 15 minutes late?
Calm-weather odds: 35% · changed +0 pts in 24h
+0 pts
41%
Yes 41%
No 59%
Leave SAN more than 15 minutes late?
Calm-weather odds: 45% · changed +5 pts in 24h
+5 pts
52%
Yes 52%
No 48%
Arrive at DEN more than an hour late?
Calm-weather odds: 8% · 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 DEN?
On time or early
58%
15–30 min late
15%
30 min–1 hour late
16%
1–2 hours late
8%
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
↑
Arrivals into DEN at that hour are often late
↑
4pm departures from SAN are often late
↑
Later flights pick up delays from earlier in the day
↓
Mostly benign weather forecast at DEN
↓
DEN usually runs smoothly
Weather at each end
SAN (origin)
Gusts 14 kt Ceiling none (clear) Visibility 10+ mi Precip none
DEN (destination)
Gusts 24 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.