Schedule: a typical summer Friday (the flights of Jul 31, 2026), re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.
SOUTHWEST · FLIGHT WN 556
SCHEDULED · TYPICAL SCHEDULE
Friday, October 2
WN 556 · STL → MDW
departs 3:35 PM CT · arrives 4:40 PM CT
Forecast issued Fri 10:00 PM ET · 5h after departure
Watch this flight
Other days
Fri 10/2
Today 33%
Mon 10/5 13%
Fri 10/9 20%
Odds over time
Arrive at MDW more than 15 minutes late?
22%
chance · ±0 pts
+0 pts · 24h
HOW SURE WE ARE
Very high. The odds now come almost entirely from live conditions.
Arrive 15+ late
22%
Leave 15+ late
31%
Arrive 1h+ late
4%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
3.8d
2d
1d
12h
6h
Departs
Lands
Arrive at MDW more than 15 minutes late?
Calm-weather odds: 22% · changed +0 pts in 24h
+0 pts
22%
Yes 22%
No 78%
Leave STL more than 15 minutes late?
Calm-weather odds: 31% · changed −3 pts in 24h
−3 pts
31%
Yes 31%
No 69%
Arrive at MDW more than an hour late?
Calm-weather odds: 4% · changed −1 pt in 24h
−1 pt
4%
Yes 4%
No 96%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 99%
How late will it get to MDW?
On time or early
77%
15–30 min late
10%
30 min–1 hour late
9%
1–2 hours late
3%
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
↑
Other factors
↑
Arrivals into MDW at that hour are often late
↑
3pm departures from STL are often late
↓
Cloud base down to 600 ft forecast at STL that day
↓
STL usually runs smoothly
Weather at each end
STL (origin)
Gusts 20 kt Ceiling 600 ft Visibility 9 mi Precip 0.01 in
MDW (destination)
Gusts 15 kt Ceiling 900 ft Visibility 7 mi Precip 0.12 in
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.