Today looks rough: weather pushes the average chance of arriving 15+ min late to 43%, against 27% on a calm day. Safest: AS 774 at 20:55, 27%.

Safest bet today AS 774 PDX 20:55 → LAS 23:10 · 27% chance 15+ min late Riskiest WN 2109 PDX 19:30 → LAS 21:45 · 52% chance 15+ min late

Weather 43% average chance a nonstop arrives 15+ min late; 27% 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. 14 flights that already left today are not shown.


AS 774 Alaska	PDX 20:55	LAS 23:10	27%	10%	0.4%	no record
WN 3174 Southwest	PDX 20:55	LAS 23:12	50%	20%	0.3%	no record
WN 2109 Southwest	PDX 19:30	LAS 21:45	52%	23%	0.3%	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 Sun, Oct 4 (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