Today looks like a normal day here: all 4 nonstops are 16–21% likely to arrive 15+ min late.

Safest bet today WN 408 BUF 14:31 → MDW 14:46 · 16% chance 15+ min late Riskiest WN 768 BUF 19:55 → MDW 20:35 · 21% chance 15+ min late · usually 60% on time

Against a calm day 19% average chance a nonstop arrives 15+ min late; 14% 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. 2 flights that already left today are not shown.


WN 408 Southwest	BUF 14:31	MDW 14:46	16%	4%	0.2%	no record
WN 766 Southwest Flight history →	BUF 16:10	MDW 16:50	17%	4%	0.2%	56%
WN 840 Southwest	BUF 19:35	MDW 20:27	20%	3%	0.2%	no record
WN 768 Southwest Flight history →	BUF 19:55	MDW 20:35	21%	4%	0.2%	60%

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