Today: DL 690 at 10:37 is the safest bet, 17% chance of being 15+ min late; the others run 17–35%.

Safest bet today DL 690 RSW 10:37 → BOS 13:46 · 17% chance 15+ min late Riskiest B6 2066 RSW 20:43 → BOS 23:56 · 35% chance 15+ min late · usually 60% on time

Against a calm day 24% average chance a nonstop arrives 15+ min late; 18% 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.


DL 690 Delta	RSW 10:37	BOS 13:46	17%	7%	0.4%	no record
DL 2373 Delta Flight history →	RSW 10:41	BOS 13:59	17%	7%	0.4%	84%
B6 266 JetBlue Flight history →	RSW 10:17	BOS 13:34	26%	14%	0.7%	68%
B6 2066 JetBlue Flight history →	RSW 20:43	BOS 23:56	35%	16%	2.7%	60%

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