Schedule: a typical Saturday (the flights of Jul 25, 2026, re-dated). Real flights replace these once the FAA publishes them, usually about a day ahead.
SOUTHWEST · FLIGHT WN 3937
SCHEDULED · TYPICAL SCHEDULE
Saturday, October 3
WN 3937 · ATL → STL
departs 8:55 AM ET · arrives 9:35 AM CT
Forecast issued Wed 11:00 AM ET · 70h before departure
Watch this flight
Other days
Today 4%
Thu 10/1 6%
Fri 10/2 8%
Sat 10/3
Mon 10/5 6%
Tue 10/6 4%
Odds over time
Arrive at STL more than 15 minutes late?
9%
chance · ±1 pts
– · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
9%
Leave 15+ late
5%
Arrive 1h+ late
1%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
5%
10%
15%
20%
4.5d
Now
2d
1d
12h
6h
Departs
Lands
Arrive at STL more than 15 minutes late?
Calm-weather odds: 6% · changed – in 24h
–
9%
Yes 9%
No 91%
Leave ATL more than 15 minutes late?
Calm-weather odds: 5% · changed – in 24h
–
5%
Yes 5%
No 95%
Arrive at STL more than an hour late?
Calm-weather odds: <1% · changed – in 24h
–
1%
Yes 1%
No 99%
Cancelled?
Calm-weather odds: <1% · changed – in 24h
–
<1%
Yes <1%
No 99%
How late will it get to STL?
On time or early
90%
15–30 min late
6%
30 min–1 hour late
2%
1–2 hours late
<1%
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
↑
ATL is busy at that time
↓
Arrivals into STL at that hour are usually not late
↓
WN's recent on-time record
Weather at each end
ATL (origin)
Gusts 5 kt Ceiling 300 ft Visibility 4 mi Precip none
STL (destination)
Gusts 10 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.