Today looks rough: weather pushes the average chance of arriving 15+ min late to 48%, against 32% on a calm day. Safest: UA 787 at 20:25, 35%.

Safest bet today UA 787 IAH 20:25 → ORD 23:15 · 35% chance 15+ min late · usually 72% on time Riskiest F9 3136 IAH 18:47 → ORD 21:30 · 67% chance 15+ min late · usually 67% on time

Weather 48% average chance a nonstop arrives 15+ min late; 32% 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. 23 flights that already left today are not shown.


UA 787 United Flight history →	IAH 20:25	ORD 23:15	35%	11%	0.2%	72%
UA 1752 United Flight history →	IAH 22:08	ORD 00:45	35%	7%	0.2%	71%
AA 4426 American flown by Republic Flight history →	IAH 17:02	ORD 20:24	36%	6%	0.2%	77%worse than usual
UA 2135 United Flight history →	IAH 17:09	ORD 20:05	43%	11%	0.2%	68%worse than usual
UA 2197 United Flight history →	IAH 18:44	ORD 21:40	43%	12%	0.2%	69%worse than usual
WN 2044 Southwest Flight history →	HOU 21:20	MDW 23:50	48%	9%	0.3%	38%
AA 1913 American Flight history →	IAH 18:48	ORD 22:01	49%	19%	0.3%	47%
WN 2088 Southwest	HOU 19:06	MDW 21:35	49%	8%	0.3%	no record
WN 4944 Southwest	HOU 19:10	MDW 21:35	50%	9%	0.3%	no record
AA 2302 American	IAH 17:08	ORD 20:09	51%	17%	0.4%	no record
UA 2786 United	IAH 17:13	ORD 19:47	52%	11%	0.2%	no record
AA 2243 American	IAH 18:48	ORD 21:32	52%	20%	0.3%	no record
WN 4789 Southwest	HOU 22:30	MDW 01:00	53%	8%	0.4%	no record
WN 2103 Southwest	HOU 15:55	MDW 18:24	55%	11%	0.6%	no record
F9 3136 Frontier Flight history →	IAH 18:47	ORD 21:30	67%	24%	0.7%	67%worse than usual

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