Today looks rough: weather pushes the average chance of arriving 15+ min late to 62%, against 41% on a calm day. Safest: UA 2050 at 18:05, 55%.

Safest bet today UA 2050 IAH 18:05 → ATL 21:18 · 55% chance 15+ min late · usually 46% on time Riskiest F9 2400 IAH 20:02 → ATL 23:24 · 74% chance 15+ min late · usually 55% on time

Weather 62% average chance a nonstop arrives 15+ min late; 41% 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. 12 flights that already left today are not shown.


UA 2050 United Flight history →	IAH 18:05	ATL 21:18	55%	13%	0.3%	46%
UA 2240 United	IAH 18:05	ATL 21:10	58%	12%	0.3%	no record
DL 1223 Delta Flight history →	IAH 18:34	ATL 21:54	58%	12%	0.4%	72%worse than usual
DL 2890 Delta Flight history →	IAH 16:51	ATL 20:13	58%	17%	0.4%	59%worse than usual
DL 1651 Delta Flight history →	IAH 18:53	ATL 21:57	60%	11%	0.4%	55%worse than usual
F9 4106 Frontier Flight history →	IAH 21:00	ATL 00:18	69%	25%	1.1%	56%worse than usual
F9 2400 Frontier Flight history →	IAH 20:02	ATL 23:24	74%	29%	1.3%	55%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 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