Schedule: the flights that flew on Monday, Nov 2, re-dated. Real flights replace these once airlines file their FAA flight plans, usually about a day ahead.
SOUTHWEST · FLIGHT WN 4431
SCHEDULED · TYPICAL SCHEDULE
Monday, November 9
WN 4431 · STL → BOS
departs 7:50 PM CT · arrives 11:39 PM ET
Forecast issued Sat 4:00 AM ET · 65h before departure
Watch this flight
Other days
Sun 11/8 36%
Mon 11/9
Tue 11/10 38%
Wed 11/11 45%
Thu 11/12 36%
Fri 11/13 44%
Odds over time
Arrive at BOS more than 15 minutes late?
22%
chance · ±1 pts
– · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
22%
Leave 15+ late
34%
Arrive 1h+ late
5%
Cancelled
<1%
MOSTLY HISTORY
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
6.9d
Now
2d
1d
12h
6h
Departs
Lands
Arrive at BOS more than 15 minutes late?
Calm-weather odds: 22% · changed – in 24h
–
22%
Yes 22%
No 78%
Leave STL more than 15 minutes late?
Calm-weather odds: 34% · changed – in 24h
–
34%
Yes 34%
No 66%
Arrive at BOS more than an hour late?
Calm-weather odds: 5% · changed – in 24h
–
5%
Yes 5%
No 95%
Cancelled?
Calm-weather odds: <1% · changed – in 24h
–
<1%
Yes <1%
No 99%
How late will it get to BOS?
On time or early
78%
15–30 min late
10%
30 min–1 hour late
7%
1–2 hours late
3%
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
↑
WN's recent on-time record
↑
This flight has been late 22% of the time recently
↑
7pm departures from STL are often late
↓
Mostly benign weather forecast at STL
↓
Mondays in November are usually quieter than average
Weather at each end
STL (origin)
Gusts 8 kt Ceiling none (clear) Visibility 10+ mi Precip none
BOS (destination)
Gusts 22 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.