Today: UA 1148 at 23:43 is the safest bet, 21% chance of being 15+ min late; the others run 24–35%.

Safest bet today UA 1148 SMF 23:43 → ORD 05:54 · 21% chance 15+ min late · usually 87% on time Riskiest AA 2627 SMF 15:05 → ORD 21:35 · 35% chance 15+ min late · usually 67% on time

Against a calm day 28% average chance a nonstop arrives 15+ min late; 27% 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. 4 flights that already left today are not shown.


UA 1148 United Flight history →	SMF 23:43	ORD 05:54	21%	4%	0.3%	87%
AA 3060 American Flight history →	SMF 23:10	ORD 05:36	24%	5%	0.2%	94%worse than usual
AA 1906 American	SMF 15:15	ORD 21:39	33%	11%	0.4%	no record
AA 2627 American Flight history →	SMF 15:05	ORD 21:35	35%	10%	0.3%	67%

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 Sun, Oct 4 (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