Schedule: a typical Tuesday (the flights of Jul 28, 2026, re-dated). Real flights replace these once the FAA publishes them, usually about a day ahead.
SOUTHWEST · FLIGHT WN 3912
SCHEDULED · TYPICAL SCHEDULE
Tuesday, September 29 Today
WN 3912 · STL → DEN
departs 4:00 PM CT · arrives 5:20 PM MT
Forecast issued Tue 5:00 PM ET · 0h before departure
Watch this flight
Other days
Today
Wed 9/30 65%
Thu 10/1 37%
Fri 10/2 27%
Sat 10/3 36%
Sun 10/4 22%
Mon 10/5 22%
Odds over time
Arrive at DEN more than 15 minutes late?
22%
chance · ±3 pts
−5 pts · 24h
HOW SURE WE ARE
Very high. The odds now come almost entirely from live conditions.
Arrive 15+ late
22%
Leave 15+ late
26%
Arrive 1h+ late
5%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
2.9d
2d
1d
12h
6h
Departs
Lands
Arrive at DEN more than 15 minutes late?
Calm-weather odds: 22% · changed −5 pts in 24h
−5 pts
22%
Yes 22%
No 78%
Leave STL more than 15 minutes late?
Calm-weather odds: 26% · changed −5 pts in 24h
−5 pts
26%
Yes 26%
No 74%
Arrive at DEN more than an hour late?
Calm-weather odds: 5% · 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 DEN?
On time or early
78%
15–30 min late
10%
30 min–1 hour late
7%
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
↓
Tuesdays in September are usually quieter than average
↓
Mostly benign weather forecast at DEN
Weather at each end
STL (origin)
Gusts 10 kt Ceiling none (clear) Visibility 10+ mi Precip none
DEN (destination)
Gusts 9 kt Ceiling 6,000 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.