Today: DL 826 at 20:59 is the safest bet, 25% chance of being 15+ min late; the others run 35–40%.

Safest bet today DL 826 ATL 20:59 → SNA 22:25 · 25% chance 15+ min late · usually 79% on time Riskiest DL 2012 ATL 17:30 → SNA 19:00 · 40% chance 15+ min late · usually 71% on time

Against a calm day 33% average chance a nonstop arrives 15+ min late; 28% 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.


DL 826 Delta Flight history →	ATL 20:59	SNA 22:25	25%	3%	0.7%	79%
DL 329 Delta Flight history →	ATL 11:00	SNA 12:31	35%	4%	0.2%	75%
DL 2012 Delta Flight history →	ATL 17:30	SNA 19:00	40%	4%	0.3%	71%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