Monday, October 5 · our forecast odds · issued Sun 4:00 PM ET · 9 nonstops

Tomorrow: WN 816 at 05:25 is the safest bet, 2% chance of being 15+ min late; evening flights run 18–22%.

Safest bet that day WN 816 BOS 05:25 → STL 07:36 · 2% chance 15+ min late Riskiest WN 4917 BOS 12:55 → STL 14:45 · 27% chance 15+ min late · usually 61% on time

Against a calm day 14% average chance a nonstop arrives 15+ min late; 13% for the same flights on a calm-weather day

Every nonstop on Mon, Oct 5

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.


WN 816 Southwest	BOS 05:25	STL 07:36	2%	1%	0.2%	no record
WN 752 Southwest Flight history →	BOS 05:35	STL 07:25	5%	1%	0.6%	100%
MQ 3546 Envoy	BOS 07:17	STL 09:39	9%	3%	0.7%	no record
AA 3814 American flown by Envoy Flight history →	BOS 07:00	STL 09:09	11%	2%	0.7%	90%
WN 1015 Southwest	BOS 11:50	STL 14:05	16%	4%	0.6%	no record
YX 4512 Republic	BOS 15:36	STL 17:59	18%	5%	0.7%	no record
AA 4678 American flown by Republic Flight history →	BOS 17:12	STL 19:21	18%	8%	0.7%	56%
WN 754 Southwest Flight history →	BOS 18:50	STL 20:55	22%	7%	0.6%	42%
WN 4917 Southwest Flight history →	BOS 12:55	STL 14:45	27%	4%	0.5%	61%

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