Today looks rough: weather pushes the average chance of arriving 15+ min late to 56%, against 30% on a calm day. Safest: WN 459 at 21:25, 48%.

Safest bet today WN 459 BNA 21:25 → BOS 00:55 · 48% chance 15+ min late · usually 43% on time Riskiest B6 406 BNA 16:16 → BOS 19:59 · 66% chance 15+ min late

Weather 56% average chance a nonstop arrives 15+ min late; 30% 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. 10 flights that already left today are not shown.


WN 459 Southwest Flight history →	BNA 21:25	BOS 00:55	48%	9%	0.2%	43%
DL 2677 Delta Flight history →	BNA 17:35	BOS 21:19	49%	19%	0.2%	64%worse than usual
WN 192 Southwest	BNA 20:35	BOS 00:06	50%	10%	0.2%	no record
B6 506 JetBlue Flight history →	BNA 19:45	BOS 23:21	60%	14%	0.3%	63%worse than usual
WN 4372 Southwest Flight history →	BNA 15:50	BOS 19:25	60%	14%	0.2%	38%
B6 406 JetBlue	BNA 16:16	BOS 19:59	66%	22%	0.5%	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