Saturday, October 10 · typical odds for a Saturday (too early for a weather forecast) · issued Sun 8:00 PM ET · 3 nonstops

Sat, Oct 10: WN 4231 at 10:42 is the safest bet, 11% chance of being 15+ min late; the others run 23%.

Safest bet that day WN 4231 SAN 10:42 → BOI 14:01 · 11% chance 15+ min late Riskiest WN 3627 SAN 18:19 → BOI 21:35 · 23% chance 15+ min late

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.


WN 4231 Southwest	SAN 10:42	BOI 14:01	11%	3%	0.6%	no record
WN 3627 Southwest	SAN 18:19	BOI 21:35	23%	6%	0.7%	no record
AS 2341 Alaska flown by Horizon no forecast: 12-month record	SAN 10:30	BOI 13:46	25%	4%	0.0%	75%

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