Today: WN 864 at 05:15 is the safest bet, 5% chance of being 15+ min late; evening flights run 22–26%.

Safest bet today WN 864 ONT 05:15 → PHX 06:30 · 5% chance 15+ min late · usually 98% on time Riskiest AA 2639 ONT 19:15 → PHX 20:36 · 26% chance 15+ min late · usually 62% on time

Against a calm day 18% average chance a nonstop arrives 15+ min late; 16% for the same flights on a calm-weather day

Every nonstop today

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 864 Southwest Flight history →	ONT 05:15	PHX 06:30	5%	1%	0.3%	98%
AA 1194 American Flight history →	ONT 06:11	PHX 07:30	9%	4%	0.5%	92%
WN 3275 Southwest	ONT 08:20	PHX 09:42	13%	2%	0.3%	no record
WN 4421 Southwest Flight history →	ONT 08:00	PHX 09:15	15%	2%	0.3%	96%worse than usual
MQ 4171 Envoy	ONT 09:44	PHX 11:14	15%	4%	0.6%	no record
WN 3062 Southwest Flight history →	ONT 12:45	PHX 14:00	16%	3%	0.4%	88%
WN 3276 Southwest	ONT 13:05	PHX 14:27	19%	3%	0.4%	no record
AA 2661 American Flight history →	ONT 13:09	PHX 14:35	19%	5%	1.3%	79%
AA 2244 American Flight history →	ONT 13:11	PHX 14:33	19%	5%	1.3%	86%
WN 3159 Southwest Flight history →	ONT 17:15	PHX 18:35	22%	5%	0.5%	73%
WN 3160 Southwest Flight history →	ONT 20:45	PHX 22:00	22%	8%	0.5%	48%
WN 3277 Southwest	ONT 16:15	PHX 17:37	22%	5%	0.4%	no record
AA 1666 American Flight history →	ONT 19:32	PHX 20:54	24%	6%	1.2%	78%
AA 2859 American Flight history →	ONT 16:27	PHX 17:51	25%	6%	1.2%	74%
AA 2639 American Flight history →	ONT 19:15	PHX 20:36	26%	9%	1.2%	62%

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