Schedule: a typical Tuesday (the flights of Jul 28, 2026, re-dated). Real flights replace these once the FAA publishes them, usually about a day ahead.
SOUTHWEST · FLIGHT WN 21
SCHEDULED · TYPICAL SCHEDULE
Tuesday, September 29 Today
WN 21 · PHX → SMF
departs 11:30 AM MT · arrives 1:25 PM PT
Forecast issued Tue 7:00 PM ET · 4h after departure
Watch this flight
Other days
Today
Wed 9/30 20%
Odds over time
Arrive at SMF more than 15 minutes late?
37%
chance · ±0 pts
+5 pts · 24h
HOW SURE WE ARE
Very high. The odds now come almost entirely from live conditions.
Arrive 15+ late
37%
Leave 15+ late
36%
Arrive 1h+ late
8%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
20%
40%
60%
80%
2.9d
2d
1d
12h
6h
Departs
Lands
Arrive at SMF more than 15 minutes late?
Calm-weather odds: 37% · changed +5 pts in 24h
+5 pts
37%
Yes 37%
No 63%
Leave PHX more than 15 minutes late?
Calm-weather odds: 36% · changed −2 pts in 24h
−2 pts
36%
Yes 36%
No 64%
Arrive at SMF more than an hour late?
Calm-weather odds: 8% · changed +3 pts in 24h
+3 pts
8%
Yes 8%
No 92%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 99%
How late will it get to SMF?
On time or early
62%
15–30 min late
17%
30 min–1 hour late
13%
1–2 hours late
6%
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
↑
Cloud base down to 1,300 ft, visibility down to 0.5 mi, 0.3 in of rain, thunderstorms forecast at PHX that day
↑
11am departures from PHX are often late
↑
PHX is busy at that time
↓
Tuesdays in September are usually quieter than average
↓
Mostly benign weather forecast at SMF
Weather at each end
PHX (origin)
Gusts 21 kt Ceiling 1,300 ft Visibility 0.5 mi Precip 0.33 in
SMF (destination)
Gusts 23 kt Ceiling none (clear) Visibility 9 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.