Today: WN 1207 at 08:20 is the safest bet, 6% chance of being 15+ min late; evening flights run 14–18%.

Safest bet today WN 1207 CLE 08:20 → MDW 08:48 · 6% chance 15+ min late Riskiest UA 3778 CLE 21:28 → MDW 22:04 · 18% chance 15+ min late

Against a calm day 13% average chance a nonstop arrives 15+ min late; 13% 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.


WN 1207 Southwest	CLE 08:20	MDW 08:48	6%	2%	0.2%	no record
WN 4171 Southwest Flight history →	CLE 08:55	MDW 09:10	8%	2%	0.2%	88%
WN 1209 Southwest	CLE 14:40	MDW 15:07	10%	2%	0.1%	no record
WN 1161 Southwest Flight history →	CLE 12:05	MDW 12:20	11%	2%	0.1%	88%
WN 1162 Southwest Flight history →	CLE 16:45	MDW 17:05	14%	3%	0.2%	82%
WN 1163 Southwest Flight history →	CLE 20:10	MDW 20:25	18%	3%	0.6%	71%
WN 2068 Southwest	CLE 20:20	MDW 20:47	18%	3%	0.6%	no record
UA 3778 United	CLE 21:28	MDW 22:04	18%	3%	0.7%	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 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