Today looks like a normal day here: all 3 nonstops are 14–16% likely to arrive 15+ min late.

Safest bet today WN 3320 PDX 23:35 → MDW 05:41 · 14% chance 15+ min late Riskiest WN 3202 PDX 11:50 → MDW 17:45 · 16% chance 15+ min late · usually 63% on time

Against a calm day 15% average chance a nonstop arrives 15+ min late; 14% 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. 2 flights that already left today are not shown.


WN 3320 Southwest	PDX 23:35	MDW 05:41	14%	3%	0.6%	no record
WN 3203 Southwest Flight history →	PDX 23:30	MDW 05:20	15%	3%	0.6%	89%
WN 3202 Southwest Flight history →	PDX 11:50	MDW 17:45	16%	3%	0.1%	63%

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