Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Mon 12:00 PM ET · 3 nonstops

Fri, Oct 9 looks like a normal day here: all 2 nonstops are 8–10% likely to arrive 15+ min late.

Safest bet that day UA 1108 IAD 08:25 → CHS 10:11 · 8% chance 15+ min late · usually 94% on time Riskiest UA 3487 IAD 12:35 → CHS 14:27 · 10% chance 15+ min late · usually 90% 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. Dimmed: airlines we don’t forecast yet, shown with their 12-month record if they usually fly that weekday.


UA 1108 United Flight history →	IAD 08:25	CHS 10:11	8%	3%	1.1%	94%
UA 3487 United flown by Republic Flight history →	IAD 12:35	CHS 14:27	10%	2%	0.9%	90%
UA 4310 United flown by CommuteAir no forecast: 12-month record	IAD 17:15	CHS 19:07	33%	24%	5.7%	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 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