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 4221
SCHEDULED · TYPICAL SCHEDULE
Wednesday, September 30 Yesterday
WN 4221 · MDW → RDU
departs 6:10 PM CT · arrives 9:10 PM ET
Forecast issued Wed 10:00 PM ET · 3h after departure
Watch this flight
Other days
Wed 9/30
Today 75%
Fri 10/2 33%
Mon 10/5 22%
Tue 10/6 28%
Wed 10/7 21%
Odds over time
Arrive at RDU more than 15 minutes late?
50%
chance · ±0 pts
+0 pts · 24h
HOW SURE WE ARE
Very high. The odds now come almost entirely from live conditions.
Arrive 15+ late
50%
Leave 15+ late
57%
Arrive 1h+ late
9%
Cancelled
3%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
20%
40%
60%
80%
2.8d
2d
1d
12h
6h
Departs
Lands
Now
Arrive at RDU more than 15 minutes late?
Calm-weather odds: 50% · changed +0 pts in 24h
+0 pts
50%
Yes 50%
No 50%
Leave MDW more than 15 minutes late?
Calm-weather odds: 57% · changed +0 pts in 24h
+0 pts
57%
Yes 57%
No 43%
Arrive at RDU more than an hour late?
Calm-weather odds: 9% · changed −3 pts in 24h
−3 pts
9%
Yes 9%
No 91%
Cancelled?
Calm-weather odds: 3% · changed +0 pts in 24h
+0 pts
3%
Yes 3%
No 97%
How late will it get to RDU?
On time or early
49%
15–30 min late
25%
30 min–1 hour late
14%
1–2 hours late
6%
Over 2 hours late
3%
Cancelled
3%
Gate arrival compared with the scheduled arrival. The ranges add up to 100%.
What’s moving the odds
↑
Cloud base down to 800 ft, visibility down to 2.5 mi, 0.8 in of rain forecast at MDW that day
↑
6pm departures from MDW are often late
↑
Later flights pick up delays from earlier in the day
↓
Wednesdays in September are usually quieter than average
↓
Mostly benign weather forecast at RDU
Weather at each end
MDW (origin)
Gusts 21 kt Ceiling 700 ft Visibility 2.5 mi Precip 0.94 in
RDU (destination)
Gusts 6 kt Ceiling none (clear) Visibility 4 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.