Monday, October 5 · our forecast odds · issued Sun 2:00 PM ET · 3 nonstops

Tomorrow: WN 4218 at 07:40 is the safest bet, 10% chance of being 15+ min late; the others run 11–26%.

Safest bet that day WN 4218 DAL 07:40 → SMF 09:15 · 10% chance 15+ min late · usually 71% on time Riskiest WN 4365 DAL 21:10 → SMF 22:45 · 26% chance 15+ min late · usually 27% on time

Against a calm day 16% average chance a nonstop arrives 15+ min late; 17% 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 4218 Southwest Flight history →	DAL 07:40	SMF 09:15	10%	2%	0.5%	71%
WN 2046 Southwest	DAL 09:15	SMF 10:57	11%	2%	0.5%	no record
WN 4365 Southwest Flight history →	DAL 21:10	SMF 22:45	26%	6%	0.5%	27%

Alternatives with one stop that day

All connections →


Southwest Details →	DAL 10:25 → PHX 10:55WN 1166	46m Phoenix	PHX 11:41 → SMF 13:45WN 4208	5h 20m	82%	68%

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