Sunday, October 11 · typical odds for a Sunday (too early for a weather forecast) · issued Mon 12:00 AM ET · 3 nonstops

Sun, Oct 11: AA 3921 at 08:25 is the safest bet, 15% chance of being 15+ min late; the others run 22–41%.

Safest bet that day AA 3921 ORD 08:25 → MHT 11:23 · 15% chance 15+ min late · usually 78% on time Riskiest AA 4149 ORD 19:59 → MHT 23:30 · 41% chance 15+ min late · usually 84% on time

Every nonstop on Sun, Oct 11

12-month record →

Ranked by the chance of arriving 15+ minutes late (typical odds: the weather this date has had in past years), 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.


AA 3921 American flown by Envoy Flight history →	ORD 08:25	MHT 11:23	15%	3%	0.8%	78%
AA 3720 American flown by Envoy Flight history →	ORD 13:49	MHT 17:03	22%	4%	1.9%	78%
AA 4149 American flown by Envoy Flight history →	ORD 19:59	MHT 23:30	41%	11%	3.0%	84%worse than usual

How these are worked out. Each flight’s odds are our forecast for that day (typical odds until the weather forecast covers it); 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 11 (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