Today: WN 1173 at 07:21 is the safest bet, 8% chance of being 15+ min late; evening flights run 24–29%.

Safest bet today WN 1173 BWI 07:21 → TPA 09:15 · 8% chance 15+ min late Riskiest WN 1997 BWI 17:05 → TPA 19:45 · 29% chance 15+ min late · usually 61% on time

Against a calm day 18% average chance a nonstop arrives 15+ min late; 14% 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.


WN 1173 Southwest	BWI 07:21	TPA 09:15	8%	1%	0.4%	no record
WN 1120 Southwest Flight history →	BWI 08:30	TPA 11:00	9%	1%	0.5%	95%
WN 1177 Southwest	BWI 08:40	TPA 11:18	9%	1%	0.5%	no record
WN 1178 Southwest	BWI 10:20	TPA 12:58	12%	3%	0.5%	no record
F9 2925 Frontier Flight history →	BWI 08:17	TPA 11:05	15%	6%	0.9%	73%
F9 1537 Frontier Flight history →	BWI 11:30	TPA 13:59	17%	10%	0.8%	79%
WN 4578 Southwest Flight history →	BWI 21:20	TPA 23:55	24%	8%	0.9%	69%
WN 2557 Southwest	BWI 15:31	TPA 18:09	25%	6%	0.6%	no record
WN 1123 Southwest Flight history →	BWI 19:10	TPA 21:55	26%	9%	0.9%	74%
WN 1180 Southwest	BWI 18:39	TPA 21:17	26%	10%	0.8%	no record
WN 1997 Southwest Flight history →	BWI 17:05	TPA 19:45	29%	7%	0.7%	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