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.
FRONTIER · FLIGHT F9 4578
SCHEDULED · TYPICAL SCHEDULE
Wednesday, September 30 Yesterday
F9 4578 · SAN → PHX
departs 4:38 PM PT · arrives 6:07 PM MT
Forecast issued Wed 10:00 PM ET · 2h after departure
Watch this flight
Other days
Wed 9/30
Today 64%
Fri 10/2 48%
Sat 10/3 41%
Sun 10/4 42%
Mon 10/5 44%
Tue 10/6 32%
Wed 10/7 33%
Odds over time
Arrive at PHX more than 15 minutes late?
37%
chance · ±1 pts
−8 pts · 24h
HOW SURE WE ARE
Very high. The odds now come almost entirely from live conditions.
Arrive 15+ late
37%
Leave 15+ late
33%
Arrive 1h+ late
12%
Cancelled
1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
20%
40%
60%
80%
2.9d
2d
1d
12h
6h
Departs
Lands
Now
Arrive at PHX more than 15 minutes late?
Calm-weather odds: 37% · changed −8 pts in 24h
−8 pts
37%
Yes 37%
No 63%
Leave SAN more than 15 minutes late?
Calm-weather odds: 33% · changed −5 pts in 24h
−5 pts
33%
Yes 33%
No 67%
Arrive at PHX more than an hour late?
Calm-weather odds: 12% · changed −1 pt in 24h
−1 pt
12%
Yes 12%
No 88%
Cancelled?
Calm-weather odds: 1% · changed +0 pts in 24h
+0 pts
1%
Yes 1%
No 99%
How late will it get to PHX?
On time or early
62%
15–30 min late
15%
30 min–1 hour late
10%
1–2 hours late
8%
Over 2 hours late
3%
Cancelled
1%
Gate arrival compared with the scheduled arrival. The ranges add up to 100%.
What’s moving the odds
↑
F9's recent on-time record
↑
4pm departures from SAN are often late
↑
Arrivals into PHX at that hour are often late
↓
Mostly benign weather forecast at PHX
↓
Wednesdays in September are usually quieter than average
Weather at each end
SAN (origin)
Gusts 17 kt Ceiling 700 ft Visibility 8 mi Precip none
PHX (destination)
Gusts 9 kt Ceiling 11,000 ft 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.