Today looks like a normal day here: all 4 nonstops are 26–27% likely to arrive 15+ min late.

Safest bet today UA 2237 SAN 11:58 → IAH 17:25 · 26% chance 15+ min late · usually 79% on time Riskiest UA 2015 SAN 17:15 → IAH 22:36 · 27% chance 15+ min late · usually 73% on time

Against a calm day 27% average chance a nonstop arrives 15+ min late; 24% 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. 3 flights that already left today are not shown.


UA 2237 United Flight history →	SAN 11:58	IAH 17:25	26%	6%	0.2%	79%
UA 618 United Flight history →	SAN 15:10	IAH 20:31	26%	6%	0.2%	66%
UA 2025 United	SAN 16:44	IAH 21:55	26%	6%	0.2%	no record
UA 2015 United Flight history →	SAN 17:15	IAH 22:36	27%	6%	0.2%	73%

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