Today: AA 4104 at 07:04 is the safest bet, 9% chance of being 15+ min late; evening flights run 20–24%.

Safest bet today AA 4104 ORD 07:04 → STL 08:31 · 9% chance 15+ min late · usually 96% on time Riskiest AA 6352 ORD 11:15 → STL 12:41 · 28% chance 15+ min late · usually 75% on time

Against a calm day 18% average chance a nonstop arrives 15+ min late; 17% 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. Dimmed: airlines we don’t forecast yet, shown with their 12-month record if they usually fly that weekday.


AA 4104 American flown by Envoy Flight history →	ORD 07:04	STL 08:31	9%	3%	0.4%	96%
UA 5958 United flown by SkyWest Flight history →	ORD 07:05	STL 08:39	10%	5%	0.3%	82%
AA 4537 American flown by Republic Flight history →	ORD 15:07	STL 16:40	10%	3%	0.6%	80%
MQ 3620 Envoy	ORD 15:29	STL 16:44	15%	3%	0.7%	no record
AA 2208 American	ORD 09:27	STL 10:47	16%	6%	0.2%	no record
UA 1355 United Flight history →	ORD 10:40	STL 12:11	16%	4%	0.2%	91%
UA 2000 United Flight history →	ORD 14:20	STL 15:46	16%	5%	0.6%	68%
UA 1044 United	ORD 10:56	STL 12:25	16%	5%	0.2%	no record
OO 5696 SkyWest	ORD 12:45	STL 14:06	18%	5%	0.6%	no record
UA 1625 United	ORD 19:45	STL 21:04	20%	6%	0.6%	no record
AA 1004 American Flight history →	ORD 23:00	STL 00:16	21%	5%	0.9%	58%
AA 3069 American Flight history →	ORD 22:55	STL 00:15	22%	6%	0.9%	62%
AA 2444 American	ORD 19:36	STL 20:55	24%	6%	1.2%	no record
OO 6468 SkyWest	ORD 11:28	STL 12:53	28%	9%	0.4%	no record
AA 6352 American flown by SkyWest Flight history →	ORD 11:15	STL 12:41	28%	9%	0.4%	75%
UA 4581 United flown by GoJet no forecast: 12-month record	ORD 12:55	STL 14:23	20%	6%	4.2%	80%
UA 4613 United flown by GoJet no forecast: 12-month record	ORD 09:00	STL 10:34	25%	13%	1.7%	75%
UA 4576 United flown by GoJet no forecast: 12-month record	ORD 22:00	STL 23:29	30%	17%	6.5%	70%
UA 4518 United flown by GoJet no forecast: 12-month record	ORD 16:45	STL 18:13	33%	18%	3.5%	67%
UA 4416 United flown by GoJet no forecast: 12-month record	ORD 15:59	STL 17:27	37%	19%	3.9%	63%
UA 4412 United flown by GoJet no forecast: 12-month record	ORD 17:55	STL 19:23	44%	22%	2.7%	56%

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