Today: WN 1997 at 08:21 is the safest bet, 10% chance of being 15+ min late; evening flights run 26–30%.

Safest bet today WN 1997 LAS 08:21 → MKE 13:52 · 10% chance 15+ min late Riskiest WN 4795 LAS 13:55 → MKE 19:26 · 38% chance 15+ min late

Against a calm day 23% average chance a nonstop arrives 15+ min late; 20% 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 1997 Southwest	LAS 08:21	MKE 13:52	10%	2%	0.2%	no record
WN 4337 Southwest Flight history →	LAS 09:05	MKE 14:35	13%	2%	0.2%	83%
WN 4136 Southwest Flight history →	LAS 20:25	MKE 01:55	26%	7%	0.6%	62%
WN 2342 Southwest	LAS 18:40	MKE 00:11	30%	8%	0.6%	no record
WN 4795 Southwest	LAS 13:55	MKE 19:26	38%	7%	0.2%	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