Today looks rough: weather pushes the average chance of arriving 15+ min late to 66%, against 33% on a calm day. Safest: WN 534 at 18:55, 61%.

Safest bet today WN 534 BNA 18:55 → HOU 21:05 · 61% chance 15+ min late · usually 33% on time Riskiest WN 4474 BNA 22:50 → HOU 00:55 · 69% chance 15+ min late · usually 47% on time

Weather 66% average chance a nonstop arrives 15+ min late; 33% 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. 7 flights that already left today are not shown.


WN 534 Southwest Flight history →	BNA 18:55	HOU 21:05	61%	15%	0.5%	33%
WN 570 Southwest	BNA 22:38	HOU 00:55	66%	22%	0.5%	no record
WN 569 Southwest	BNA 19:28	HOU 21:15	67%	17%	0.5%	no record
WN 4474 Southwest Flight history →	BNA 22:50	HOU 00:55	69%	21%	0.5%	47%worse than usual

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