Monday, October 5 · our forecast odds · issued Sun 4:00 PM ET · 9 nonstops

Tomorrow: WN 276 at 09:17 is the safest bet, 9% chance of being 15+ min late; evening flights run 25–31%.

Safest bet that day WN 276 LAS 09:17 → ONT 10:27 · 9% chance 15+ min late Riskiest F9 1357 LAS 14:45 → ONT 15:54 · 38% chance 15+ min late · usually 82% on time

Against a calm day 24% average chance a nonstop arrives 15+ min late; 20% for the same flights on a calm-weather day

Every nonstop on Mon, Oct 5

12-month record →

Ranked by the chance of arriving 15+ minutes late, with each flight’s on-time record over Aug 2025 – Jul 2026 beside it. Times are local. Pick a flight for its forecast. Click a column to sort.


WN 276 Southwest	LAS 09:17	ONT 10:27	9%	2%	0.5%	no record
WN 4179 Southwest Flight history →	LAS 09:05	ONT 10:10	10%	2%	0.4%	82%
F9 2231 Frontier Flight history →	LAS 06:01	ONT 07:18	13%	5%	0.9%	78%
WN 2135 Southwest Flight history →	LAS 22:25	ONT 23:35	25%	6%	0.5%	23%
F9 1283 Frontier Flight history →	LAS 10:03	ONT 11:20	26%	9%	0.9%	86%worse than usual
WN 2362 Southwest	LAS 12:57	ONT 14:07	27%	5%	0.5%	no record
WN 208 Southwest Flight history →	LAS 19:10	ONT 20:10	31%	8%	0.5%	56%
WN 3845 Southwest Flight history →	LAS 14:20	ONT 15:25	33%	5%	0.5%	52%
F9 1357 Frontier Flight history →	LAS 14:45	ONT 15:54	38%	12%	0.9%	82%worse than usual

How these are worked out. Each flight’s odds are our forecast for that day; flights of airlines we don’t forecast yet use their 12-month record and are marked. Makes the connection: the first flight’s 12-month lateness curve, scaled so its chance of arriving 15+ min late matches the day’s forecast, at the layover minus the 45-minute minimum (90 on separate tickets). Arrives on time: first flight not cancelled × connection made × second flight not cancelled × second flight within 15 minutes, each from the day’s forecast.

About this data: forecast odds from our model for Mon, Oct 5 (newest published update); 12-month records from US DOT on-time data, Aug 2025 – Jul 2026, all US airlines; regional flights count under the airline that sells them. JSON