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 4487
SCHEDULED · TYPICAL SCHEDULE
Wednesday, September 30 Tomorrow
WN 4487 · LAS → COS
departs 8:55 PM PT · arrives 11:50 PM MT
Forecast issued Wed 1:00 AM ET · 23h before departure
Watch this flight
Other days
Today
Thu 10/1 30%
Fri 10/2 38%
Mon 10/5 27%
Tue 10/6 16%
Odds over time
Arrive at COS more than 15 minutes late?
35%
chance · ±10 pts
+7 pts · 24h
HOW SURE WE ARE
Good. The odds now lean mostly on firmed-up weather forecasts.
Arrive 15+ late
35%
Leave 15+ late
40%
Arrive 1h+ late
8%
Cancelled
2%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
15%
30%
45%
60%
2.9d
2d
Now
12h
6h
Departs
Lands
Arrive at COS more than 15 minutes late?
Calm-weather odds: 16% · changed +7 pts in 24h
+7 pts
35%
Yes 35%
No 65%
Leave LAS more than 15 minutes late?
Calm-weather odds: 35% · changed +5 pts in 24h
+5 pts
40%
Yes 40%
No 60%
Arrive at COS more than an hour late?
Calm-weather odds: 7% · changed +0 pts in 24h
+0 pts
8%
Yes 8%
No 92%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
2%
Yes 2%
No 98%
How late will it get to COS?
On time or early
63%
15–30 min late
13%
30 min–1 hour late
14%
1–2 hours late
6%
Over 2 hours late
2%
Cancelled
2%
Gate arrival compared with the scheduled arrival. The ranges add up to 100%.
What’s moving the odds
↑
Gusts to 40 kt, cloud base down to 1,100 ft, 0.8 in of rain forecast at COS that day
↑
WN's recent on-time record
↑
8pm departures from LAS are often late
↓
Wednesdays in September are usually quieter than average
↓
COS usually runs smoothly
Weather at each end
LAS (origin)
Gusts 16 kt Ceiling none (clear) Visibility 10+ mi Precip none
COS (destination)
Gusts 40 kt Ceiling 1,100 ft Visibility 5 mi Precip 0.82 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.