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 3912
SCHEDULED · TYPICAL SCHEDULE
Wednesday, September 30 Today
WN 3912 · STL → DEN
departs 4:00 PM CT · arrives 5:20 PM MT
Forecast issued Wed 3:00 PM ET · 2h before departure
Watch this flight
Other days
Today
Thu 10/1 41%
Fri 10/2 29%
Sat 10/3 36%
Sun 10/4 22%
Mon 10/5 22%
Tue 10/6 22%
Odds over time
Arrive at DEN more than 15 minutes late?
37%
chance · ±0 pts
−21 pts · 24h
HOW SURE WE ARE
High. The odds now come mostly from live FAA and airport data.
Arrive 15+ late
37%
Leave 15+ late
36%
Arrive 1h+ late
5%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
25%
50%
75%
100%
2.9d
2d
1d
12h
6h
Now
Departs
Lands
Arrive at DEN more than 15 minutes late?
Calm-weather odds: 25% · changed −21 pts in 24h
−21 pts
37%
Yes 37%
No 63%
Leave STL more than 15 minutes late?
Calm-weather odds: 26% · changed −12 pts in 24h
−12 pts
36%
Yes 36%
No 64%
Arrive at DEN more than an hour late?
Calm-weather odds: 4% · changed −22 pts in 24h
−22 pts
5%
Yes 5%
No 95%
Cancelled?
Calm-weather odds: <1% · changed −1 pt in 24h
−1 pt
<1%
Yes <1%
No 100%
How late will it get to DEN?
On time or early
63%
15–30 min late
24%
30 min–1 hour late
8%
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
↑
Arrivals into DEN at that hour are often late
↑
4pm departures from STL are often late
↑
This flight has been late 33% of the time recently
↓
Wednesdays in September are usually quieter than average
↓
Mostly benign weather forecast at STL
Weather at each end
STL (origin)
Gusts 14 kt Ceiling 9,000 ft Visibility 10+ mi Precip none
DEN (destination)
Gusts 15 kt Ceiling 7,000 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.