Schedule: a typical summer Monday (the flights of Jul 27, 2026), re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.
SOUTHWEST · FLIGHT WN 4437
SCHEDULED · TYPICAL SCHEDULE
Monday, October 5
WN 4437 · BWI → GSP
departs 8:00 PM ET · arrives 9:40 PM ET
Forecast issued Sat 10:00 PM ET · 46h before departure
Watch this flight
Other days
Today 31%
Sun 10/4 44%
Mon 10/5
Fri 10/9 24%
Odds over time
Arrive at GSP more than 15 minutes late?
22%
chance · ±2 pts
−1 pt · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
22%
Leave 15+ late
32%
Arrive 1h+ late
5%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
10%
20%
30%
40%
6.8d
Now
1d
12h
6h
Departs
Lands
Arrive at GSP more than 15 minutes late?
Calm-weather odds: 20% · changed −1 pt in 24h
−1 pt
22%
Yes 22%
No 78%
Leave BWI more than 15 minutes late?
Calm-weather odds: 28% · changed −2 pts in 24h
−2 pts
32%
Yes 32%
No 68%
Arrive at GSP more than an hour late?
Calm-weather odds: 5% · changed −1 pt in 24h
−1 pt
5%
Yes 5%
No 95%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 99%
How late will it get to GSP?
On time or early
77%
15–30 min late
5%
30 min–1 hour late
12%
1–2 hours late
4%
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
↑
8pm departures from BWI are often late
↑
Later flights pick up delays from earlier in the day
↑
WN's recent on-time record
↓
Mondays in October are usually quieter than average
↓
Cloud base down to 200 ft, visibility down to 0.666667 mi forecast at BWI that day
Weather at each end
BWI (origin)
Gusts 19 kt Ceiling 100 ft Visibility 1.2 mi Precip none
GSP (destination)
Gusts 11 kt Ceiling 200 ft Visibility 0.8 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.