Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 7 nonstops

Fri, Oct 9: UA 1252 at 10:31 is the safest bet, 6% chance of being 15+ min late; evening flights run 11–24%.

Safest bet that day UA 1252 IAD 10:31 → ORD 11:53 · 6% chance 15+ min late · usually 92% on time Riskiest UA 2497 IAD 17:42 → ORD 18:50 · 24% chance 15+ min late · usually 48% on time

Every nonstop on Fri, Oct 9

12-month record →

Ranked by the chance of arriving 15+ minutes late (typical odds: the weather this date has had in past years), 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.


UA 1252 United Flight history →	IAD 10:31	ORD 11:53	6%	4%	0.6%	92%
UA 2070 United Flight history →	IAD 06:10	ORD 07:27	6%	3%	0.6%	84%
UA 1775 United Flight history →	IAD 08:15	ORD 09:36	8%	4%	0.6%	84%
UA 1738 United Flight history →	IAD 22:20	ORD 23:31	11%	4%	0.6%	80%
UA 2331 United Flight history →	IAD 13:15	ORD 14:29	13%	5%	0.6%	81%
UA 1393 United Flight history →	IAD 15:39	ORD 17:02	15%	6%	0.6%	64%
UA 2497 United Flight history →	IAD 17:42	ORD 18:50	24%	7%	0.6%	48%

How these are worked out. Each flight’s odds are our forecast for that day (typical odds until the weather forecast covers it); 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 Fri, Oct 9 (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