Saturday, October 10 · typical odds for a Saturday (too early for a weather forecast) · issued Sun 8:00 PM ET · 4 nonstops

Sat, Oct 10 looks like a normal day here: all 2 nonstops are 7–11% likely to arrive 15+ min late.

Safest bet that day UA 3561 IAD 08:24 → IND 10:13 · 7% chance 15+ min late · usually 91% on time Riskiest UA 3543 IAD 12:35 → IND 14:34 · 11% chance 15+ min late · usually 84% on time

Every nonstop on Sat, Oct 10

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. Dimmed: airlines we don’t forecast yet, shown with their 12-month record if they usually fly that weekday.


UA 3561 United flown by Republic Flight history →	IAD 08:24	IND 10:13	7%	2%	0.6%	91%
UA 3543 United flown by Republic Flight history →	IAD 12:35	IND 14:34	11%	2%	0.6%	84%
UA 3997 United flown by Mesa no forecast: 12-month record	IAD 22:16	IND 23:59	28%	9%	0.0%	72%
UA 4021 United flown by Mesa no forecast: 12-month record	IAD 22:16	IND 23:59	33%	17%	3.2%	67%

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 Sat, Oct 10 (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