Schedule: a typical summer Sunday (the flights of Jul 26, 2026), re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.
SOUTHWEST · FLIGHT WN 4577
SCHEDULED · TYPICAL SCHEDULE
Sunday, October 4
WN 4577 · DAL → MIA
departs 3:50 PM CT · arrives 7:40 PM ET
Forecast issued Fri 10:00 AM ET · 55h before departure
Watch this flight
Odds over time
Arrive at MIA more than 15 minutes late?
30%
chance · ±2 pts
– · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
30%
Leave 15+ late
42%
Arrive 1h+ late
9%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
5.8d
Now
2d
1d
12h
6h
Departs
Lands
Arrive at MIA more than 15 minutes late?
Calm-weather odds: 23% · changed – in 24h
–
30%
Yes 30%
No 70%
Leave DAL more than 15 minutes late?
Calm-weather odds: 38% · changed – in 24h
–
42%
Yes 42%
No 58%
Arrive at MIA more than an hour late?
Calm-weather odds: 6% · changed – in 24h
–
9%
Yes 9%
No 91%
Cancelled?
Calm-weather odds: <1% · changed – in 24h
–
<1%
Yes <1%
No 99%
How late will it get to MIA?
On time or early
70%
15–30 min late
11%
30 min–1 hour late
10%
1–2 hours late
8%
Over 2 hours late
2%
Cancelled
<1%
Gate arrival compared with the scheduled arrival. The ranges add up to 100%.
What’s moving the odds
↑
Later flights pick up delays from earlier in the day
↑
Arrivals into MIA at that hour are often late
↑
3pm departures from DAL are often late
↓
Sundays in October are usually quieter than average
↓
Mostly benign weather forecast at MIA
Weather at each end
DAL (origin)
Gusts 18 kt Ceiling 600 ft Visibility 10+ mi Precip 0.07 in
MIA (destination)
Gusts 20 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.