Schedule: a typical Saturday (the flights of Jul 25, 2026, re-dated). Real flights replace these once the FAA publishes them, usually about a day ahead.
FRONTIER · FLIGHT F9 4278
SCHEDULED · TYPICAL SCHEDULE
Saturday, October 3
F9 4278 · LAS → IAD
departs 12:46 AM PT · arrives 8:20 AM ET
Forecast issued Wed 9:00 PM ET · 55h before departure
Watch this flight
Other days
Today 24%
Thu 10/1 24%
Fri 10/2 24%
Sat 10/3
Sun 10/4 25%
Mon 10/5 27%
Tue 10/6 19%
Odds over time
Arrive at IAD more than 15 minutes late?
20%
chance · ±2 pts
−1 pt · 24h
HOW SURE WE ARE
Moderate. The odds now blend history with early weather forecasts.
Arrive 15+ late
20%
Leave 15+ late
28%
Arrive 1h+ late
6%
Cancelled
<1%
WEATHER FORECASTS
LIVE
IN THE AIR
0%
10%
20%
30%
40%
4.2d
Now
2d
1d
12h
6h
Departs
Lands
Arrive at IAD more than 15 minutes late?
Calm-weather odds: 22% · changed −1 pt in 24h
−1 pt
20%
Yes 20%
No 80%
Leave LAS more than 15 minutes late?
Calm-weather odds: 28% · changed −2 pts in 24h
−2 pts
28%
Yes 28%
No 72%
Arrive at IAD more than an hour late?
Calm-weather odds: 6% · changed +0 pts in 24h
+0 pts
6%
Yes 6%
No 94%
Cancelled?
Calm-weather odds: <1% · changed +0 pts in 24h
+0 pts
<1%
Yes <1%
No 99%
How late will it get to IAD?
On time or early
79%
15–30 min late
8%
30 min–1 hour late
6%
1–2 hours late
4%
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
↑
F9's recent on-time record
↑
This flight has been late 32% of the time recently
↑
12am departures from LAS are often late
↓
Mostly benign weather forecast at LAS
↓
IAD usually runs smoothly
Weather at each end
LAS (origin)
Gusts 11 kt Ceiling none (clear) Visibility 10+ mi Precip none
IAD (destination)
Gusts 15 kt Ceiling 2,600 ft Visibility 7 mi Precip 0.04 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.