Today looks rough: weather pushes the average chance of arriving 15+ min late to 51%, against 38% on a calm day. Safest: DL 512 at 13:59, 43%.

Safest bet today DL 512 ATL 13:59 → DAL 15:03 · 43% chance 15+ min late · usually 86% on time Riskiest WN 206 ATL 20:13 → DAL 21:32 · 60% chance 15+ min late

Weather 51% average chance a nonstop arrives 15+ min late; 38% 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. 6 flights that already left today are not shown.


DL 512 Delta Flight history →	ATL 13:59	DAL 15:03	43%	7%	0.6%	86%worse than usual
WN 2320 Southwest	ATL 13:50	DAL 14:55	45%	7%	0.6%	no record
DL 1104 Delta Flight history →	ATL 21:15	DAL 22:25	48%	8%	1.0%	82%worse than usual
DL 2780 Delta Flight history →	ATL 16:44	DAL 17:54	52%	10%	0.8%	79%worse than usual
WN 2981 Southwest	ATL 15:00	DAL 16:13	60%	10%	0.7%	no record
WN 206 Southwest	ATL 20:13	DAL 21:32	60%	13%	0.8%	no record

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