Holiday travel
Memorial Day at ONT
Ontario International Airport, Ontario, CA. July 2023 – July 2026. Set against ONT’s own ordinary days of the same weekday in the weeks around each holiday.
The window, year by year
The window runs the Saturday through the Monday, around Memorial Day (the last Monday of May). In the data: May 25–27, 2024; May 24–26, 2025; May 23–25, 2026. Three windows are in the data: enough to see whether a day repeats, not enough to call it a rule.
Compared with ordinary days, Memorial Day flights were better in one and about the same in two of the three years. The gap ran from 2.1 points below usual in 2025 to 7.2 points above usual in 2024.
0.79% of scheduled departures were cancelled across the Memorial Day windows, against 0.81% on ordinary days of the same weekdays. It was lower in one of the three years.
| Year | Departures | On time | Usual | Gap, points | Cancelled | Usual |
|---|---|---|---|---|---|---|
| 2024May 25–27, 2024 | 204 | 87.3% | 80.1% | +7.2better | 0.00% | 0.81% |
| 2025May 24–26, 2025 | 213 | 78.0% | 80.1% | −2.1about the same | 0.94% | 0.80% |
| 2026May 23–25, 2026 | 212 | 80.2% | 80.2% | 0.0about the same | 1.42% | 0.81% |
| All years3 windows | 629 | 81.8% | 80.1% | +1.7about the same | 0.79% | 0.81% |
Day by day
No single day has enough flights in one year to compare the years, so the days are ranked on all three years pooled: Memorial Day ran lowest (78.7% on time, about level with usual) and the Sunday before Memorial Day highest (85.6%, 7.0 points above usual). This cannot say whether the same day was worst or best in each year.
- Better than usual
- Worse than usual
- About the same
- What ordinary days of the same weekday had
- Lowest to highest single year
- Lighter bars: days just outside the window
Bars show the on-time arrival rate and start at 70%, not zero.
| Day | Departures against an ordinary day | On time | Usual | Gap, points | Cancelled | Each year: 2024, 2025, 2026 |
|---|---|---|---|---|---|---|
| Thursday beforeoutside the window | about the same | 82.2% | 79.8% | +2.4about the same | 0.82% | — · — · — |
| Friday beforeoutside the window | about the same | 79.5% | 78.2% | +1.3about the same | 0.00% | — · — · — |
| Saturday before | 2% fewer | 81.7% | 84.1% | −2.4about the same | 0.00% | — · — · — |
| Sunday before | 15% fewer | 85.6% | 78.6% | +7.0better | 0.51% | — · — · — |
| Memorial Day | about the same | 78.7% | 78.2% | +0.5about the same | 1.63% | — · — · — |
| Tuesday afteroutside the window | 2% more | 78.1% | 82.2% | −4.1about the same | 3.21% | — · — · — |
A dash means fewer than 120 flights stood behind the figure, or behind the ordinary days it would be compared with: too few to print a rate, and nothing is estimated in its place. “Usual” is what ordinary days of the same weekday had at the same place in the weeks around the holiday, weighted by the flights being compared.
Which departure times held up
The busiest days at ONT were Sunday, May 26, 2024 (64 departures), Monday, May 27, 2024 (81 departures), Sunday, May 25, 2025 (65 departures), Monday, May 26, 2025 (85 departures), Sunday, May 24, 2026 (69 departures), and Monday, May 25, 2026 (79 departures).
Across the whole window, flights leaving 5–9 AM had the highest on-time rate: 92.3%, about level with usual for that time of day. Those leaving 12–3 PM had the lowest: 76.0%, about level with usual for that time of day.
| Leaving | On time, whole window | Usual | Gap, points | On time, busiest days | Usual | Gap, points |
|---|---|---|---|---|---|---|
| 5–9 AM | 92.3% | 91.5% | +0.8about the same | 92.2% | 91.3% | +0.9about the same |
| 9 AM–12 PM | — | — | — | — | — | — |
| 12–3 PM | 76.0% | 75.1% | +0.9about the same | — | — | — |
| 3–6 PM | — | — | — | — | — | — |
| 6–9 PM | — | — | — | — | — | — |
| 9 PM–5 AM | — | — | — | — | — | — |
ONT beside every covered airport
Storms and outages move whole regions at once. This puts ONT’s year beside the year of all covered airports together, each against its own usual, to show whether ONT did better or worse than the network.
| Year | ONT on time | ONT, gap from usual | All airports on time | All airports, gap from usual |
|---|---|---|---|---|
| 2024May 25–27, 2024 | 87.3% | +7.2 | 72.7% | −2.3 |
| 2025May 24–26, 2025 | 78.0% | −2.1 | 76.4% | +1.4 |
| 2026May 23–25, 2026 | 80.2% | 0.0 | 75.0% | 0.0 |
For every holiday at once, see the five holidays at ONT, or the network view.