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 4377
SCHEDULED · TYPICAL SCHEDULE
Wednesday, September 30 Today
WN 4377 · DCA → DAL
departs 8:35 PM ET · arrives 10:55 PM CT
Forecast issued Wed 4:00 AM ET · 17h before departure
Watch this flight
Other days
Today
Thu 10/1 54%
Fri 10/2 54%
Sun 10/4 38%
Mon 10/5 30%
Tue 10/6 24%
Odds over time
Arrive at DAL more than 15 minutes late?
58%
chance · ±6 pts
+13 pts · 24h
HOW SURE WE ARE
Good. The odds now lean mostly on firmed-up weather forecasts.
Arrive 15+ late
58%
Leave 15+ late
47%
Arrive 1h+ late
21%
Cancelled
4%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
20%
40%
60%
80%
2.8d
2d
1d
Now
12h
6h
Departs
Lands
Arrive at DAL more than 15 minutes late?
Calm-weather odds: 30% · changed +13 pts in 24h
+13 pts
58%
Yes 58%
No 42%
Leave DCA more than 15 minutes late?
Calm-weather odds: 36% · changed +5 pts in 24h
+5 pts
47%
Yes 47%
No 53%
Arrive at DAL more than an hour late?
Calm-weather odds: 8% · changed +7 pts in 24h
+7 pts
21%
Yes 21%
No 79%
Cancelled?
Calm-weather odds: <1% · changed +2 pts in 24h
+2 pts
4%
Yes 4%
No 96%
How late will it get to DAL?
On time or early
40%
15–30 min late
21%
30 min–1 hour late
14%
1–2 hours late
16%
Over 2 hours late
4%
Cancelled
4%
Gate arrival compared with the scheduled arrival. The ranges add up to 100%.
What’s moving the odds
↑
Gusts to 28 kt forecast at DAL that day
↑
Arrivals into DAL at that hour are often late
↑
This flight has been late 43% of the time recently
↓
Mostly benign weather forecast at DCA
↓
Wednesdays in September are usually quieter than average
Weather at each end
DCA (origin)
Gusts 10 kt Ceiling 6,000 ft Visibility 10+ mi Precip none
DAL (destination)
Gusts 28 kt Ceiling 2,700 ft Visibility 10+ mi Precip 0.14 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.