Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 5 nonstops

Fri, Oct 9 looks like a normal day here: all 5 nonstops are 8–16% likely to arrive 15+ min late.

Safest bet that day UA 1935 IAD 06:30 → IAH 08:39 · 8% chance 15+ min late · usually 100% on time Riskiest UA 2217 IAD 17:59 → IAH 20:25 · 16% chance 15+ min late · usually 72% 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 1935 United Flight history →	IAD 06:30	IAH 08:39	8%	2%	0.6%	100%
UA 1524 United Flight history →	IAD 08:40	IAH 10:59	11%	3%	0.6%	89%
UA 1986 United Flight history →	IAD 22:20	IAH 00:45	11%	4%	0.6%	81%
UA 1535 United Flight history →	IAD 12:50	IAH 15:11	12%	4%	0.6%	84%
UA 2217 United Flight history →	IAD 17:59	IAH 20:25	16%	6%	0.7%	72%

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