Monday, October 5 · our forecast odds · issued Sun 9:00 PM ET · 4 nonstops

Tomorrow: WN 4531 at 07:35 is the safest bet, 12% chance of being 15+ min late; evening flights run 28–29%.

Safest bet that day WN 4531 DAL 07:35 → IND 10:45 · 12% chance 15+ min late · usually 90% on time Riskiest WN 2250 DAL 19:55 → IND 23:05 · 29% chance 15+ min late · usually 40% on time

Against a calm day 21% average chance a nonstop arrives 15+ min late; 20% for the same flights on a calm-weather day

Every nonstop on Mon, Oct 5

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 4531 Southwest Flight history →	DAL 07:35	IND 10:45	12%	2%	0.2%	90%
WN 4673 Southwest	DAL 10:20	IND 13:27	15%	3%	0.5%	no record
WN 2459 Southwest	DAL 20:15	IND 23:26	28%	6%	0.5%	no record
WN 2250 Southwest Flight history →	DAL 19:55	IND 23:05	29%	6%	0.5%	40%

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