Today looks rough: weather pushes the average chance of arriving 15+ min late to 54%, against 36% on a calm day. Safest: DL 5644 at 18:22, 30%.

Safest bet today DL 5644 BWI 18:22 → BOS 20:07 · 30% chance 15+ min late · usually 67% on time Riskiest WN 2288 BWI 17:36 → BOS 19:06 · 67% chance 15+ min late

Weather 54% average chance a nonstop arrives 15+ min late; 36% 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. 12 flights that already left today are not shown.


DL 5644 Delta flown by Republic Flight history →	BWI 18:22	BOS 20:07	30%	15%	0.7%	67%
WN 3018 Southwest	BWI 22:31	BOS 00:01	48%	11%	0.5%	no record
WN 3944 Southwest	BWI 21:26	BOS 22:56	52%	15%	0.5%	no record
WN 941 Southwest	BWI 19:30	BOS 21:05	62%	23%	0.5%	no record
WN 1491 Southwest	BWI 16:50	BOS 18:25	64%	17%	0.5%	no record
WN 2288 Southwest	BWI 17:36	BOS 19:06	67%	22%	0.6%	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