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 3977
SCHEDULED · TYPICAL SCHEDULE
Sunday, October 4
WN 3977 · MIA → BWI
departs 6:55 PM ET · arrives 9:35 PM ET
Forecast issued Fri 12:00 PM ET · 55h before departure
Watch this flight
Odds over time
Arrive at BWI more than 15 minutes late?
41%
chance · ±4 pts
– · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
41%
Leave 15+ late
37%
Arrive 1h+ late
14%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
5.9d
Now
2d
1d
12h
6h
Departs
Lands
Arrive at BWI more than 15 minutes late?
Calm-weather odds: 26% · changed – in 24h
–
41%
Yes 41%
No 59%
Leave MIA more than 15 minutes late?
Calm-weather odds: 32% · changed – in 24h
–
37%
Yes 37%
No 63%
Arrive at BWI more than an hour late?
Calm-weather odds: 9% · changed – in 24h
–
14%
Yes 14%
No 86%
Cancelled?
Calm-weather odds: <1% · changed – in 24h
–
<1%
Yes <1%
No 99%
How late will it get to BWI?
On time or early
58%
15–30 min late
13%
30 min–1 hour late
14%
1–2 hours late
10%
Over 2 hours late
3%
Cancelled
<1%
Gate arrival compared with the scheduled arrival. The ranges add up to 100%.
What’s moving the odds
↑
Arrivals into BWI at that hour are often late
↑
Cloud base down to 200 ft, visibility down to 1 mi, 0.4 in of rain forecast at BWI that day
↑
Later flights pick up delays from earlier in the day
↓
Sundays in October are usually quieter than average
↓
BWI usually runs smoothly
Weather at each end
MIA (origin)
Gusts 20 kt Ceiling none (clear) Visibility 10+ mi Precip none
BWI (destination)
Gusts 11 kt Ceiling 200 ft Visibility 1 mi Precip 0.42 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.