Today: WN 3366 at 10:00 is the safest bet, 12% chance of being 15+ min late; evening flights run 22–35%.

Safest bet today WN 3366 MDW 10:00 → OAK 12:30 · 12% chance 15+ min late · usually 74% on time Riskiest WN 4042 MDW 21:25 → OAK 23:55 · 35% chance 15+ min late · usually 48% on time

Against a calm day 25% average chance a nonstop arrives 15+ min late; 26% 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. 4 flights that already left today are not shown.


WN 3366 Southwest Flight history →	MDW 10:00	OAK 12:30	12%	3%	0.1%	74%
WN 4280 Southwest	MDW 10:01	OAK 12:38	12%	2%	0.1%	no record
WN 1705 Southwest	MDW 10:01	SJC 12:37	14%	2%	0.1%	no record
WN 3115 Southwest	MDW 10:05	SJC 12:30	14%	2%	0.1%	no record
UA 307 United	ORD 09:11	SJC 11:45	14%	3%	0.2%	no record
UA 342 United	ORD 08:38	SFO 11:12	17%	5%	0.2%	no record
AA 1851 American	ORD 09:46	SFO 12:28	17%	5%	0.2%	no record
UA 543 United Flight history →	ORD 10:25	SFO 13:14	17%	6%	0.2%	63%
AA 3115 American Flight history →	ORD 08:36	SFO 11:16	18%	6%	0.2%	93%worse than usual
AA 1586 American Flight history →	ORD 08:45	SFO 11:27	19%	6%	0.2%	58%
WN 1546 Southwest Flight history →	MDW 09:45	SFO 12:25	19%	4%	0.1%	12%
UA 2610 United Flight history →	ORD 08:50	SFO 11:38	20%	6%	0.3%	54%
AA 2550 American Flight history →	ORD 11:05	SFO 13:46	21%	6%	0.1%	41%
WN 4367 Southwest	MDW 10:06	SFO 12:43	21%	4%	0.1%	no record
UA 2106 United Flight history →	ORD 21:35	SFO 00:32	22%	7%	0.6%	78%
UA 1097 United Flight history →	ORD 12:35	SFO 15:08	24%	5%	0.2%	79%
UA 1334 United Flight history →	ORD 15:26	SFO 18:18	26%	7%	0.2%	66%
UA 1577 United Flight history →	ORD 14:30	SFO 17:19	26%	6%	0.2%	74%
UA 2251 United Flight history →	ORD 15:57	SFO 18:49	26%	6%	0.2%	69%
AA 2817 American	ORD 13:38	SFO 16:34	28%	5%	0.1%	no record
UA 2437 United	ORD 16:02	SFO 18:34	28%	7%	0.2%	no record
AA 1253 American Flight history →	ORD 15:18	SFO 17:58	30%	6%	0.1%	70%
WN 1940 Southwest	MDW 21:21	SJC 23:59	30%	8%	0.6%	no record
UA 1495 United Flight history →	ORD 20:04	SFO 22:57	31%	9%	0.6%	45%
UA 481 United Flight history →	ORD 19:58	SJC 22:43	32%	10%	0.6%	67%
AA 3202 American	ORD 21:38	SFO 00:19	32%	10%	0.9%	no record
AA 2856 American	ORD 19:11	SFO 22:10	33%	7%	0.2%	no record
UA 649 United	ORD 18:22	SFO 20:56	33%	7%	0.2%	no record
WN 2199 Southwest	MDW 21:31	SFO 00:10	33%	9%	0.6%	no record
WN 2015 Southwest	MDW 21:26	OAK 00:08	33%	6%	0.6%	no record
AA 3054 American Flight history →	ORD 21:17	SFO 23:59	35%	10%	0.9%	32%
AA 3141 American Flight history →	ORD 17:23	SFO 20:05	35%	7%	0.2%	57%
AA 1620 American Flight history →	ORD 18:09	SFO 20:56	35%	8%	0.2%	34%
UA 2179 United Flight history →	ORD 18:20	SFO 21:18	35%	8%	0.2%	48%
WN 4042 Southwest Flight history →	MDW 21:25	OAK 23:55	35%	7%	0.6%	48%

Alternatives with one stop that day

All connections →


United Details →	ORD 08:29 → DEN 10:20UA 526	1h 01m Denver	DEN 11:21 → SFO 13:04UA 1561	6h 35m	87%	66%
United Details →	ORD 12:56 → DEN 14:46UA 1150	1h 01m Denver	DEN 15:47 → SFO 17:30UA 2633	6h 34m	83%	59%

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