Today: WN 1775 at 07:55 is the safest bet, 8% chance of being 15+ min late; evening flights run 22–23%.

Safest bet today WN 1775 MDW 07:55 → DTW 10:05 · 8% chance 15+ min late · usually 85% on time Riskiest WN 1295 MDW 14:45 → DTW 16:58 · 26% chance 15+ min late

Against a calm day 17% average chance a nonstop arrives 15+ min late; 16% 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. Dimmed: airlines we don’t forecast yet, shown with their 12-month record if they usually fly that weekday.


WN 1775 Southwest Flight history →	MDW 07:55	DTW 10:05	8%	1%	0.2%	85%
WN 2172 Southwest	MDW 07:55	DTW 10:05	8%	1%	0.2%	no record
WN 4200 Southwest Flight history →	MDW 18:50	DTW 21:05	22%	4%	0.5%	54%
WN 2746 Southwest	MDW 19:35	DTW 21:45	23%	4%	0.6%	no record
WN 1295 Southwest	MDW 14:45	DTW 16:58	26%	3%	0.2%	no record
DL 4674 Delta flown by Endeavor no forecast: 12-month record	MDW 09:17	DTW 11:35	16%	9%	0.0%	84%
DL 4688 Delta flown by Endeavor no forecast: 12-month record	MDW 13:26	DTW 15:44	19%	13%	1.2%	81%
DL 4690 Delta flown by Endeavor no forecast: 12-month record	MDW 18:58	DTW 21:16	43%	20%	1.8%	57%

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