Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 6 nonstops

Fri, Oct 9: WN 1775 at 07:55 is the safest bet, 7% chance of being 15+ min late; the others run 14–24%.

Safest bet that day WN 1775 MDW 07:55 → DTW 10:05 · 7% chance 15+ min late · usually 85% on time Riskiest WN 4200 MDW 18:50 → DTW 21:05 · 24% chance 15+ min late · usually 54% on time

Every nonstop on Fri, Oct 9

12-month record →

Ranked by the chance of arriving 15+ minutes late (typical odds: the weather this date has had in past years), 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	7%	1%	0.6%	85%
WN 4450 Southwest Flight history →	MDW 13:10	DTW 15:20	14%	3%	0.6%	52%
WN 4200 Southwest Flight history →	MDW 18:50	DTW 21:05	24%	5%	0.6%	54%
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 (typical odds until the weather forecast covers it); 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 Fri, Oct 9 (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