Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 6 nonstops

Fri, Oct 9: WN 834 at 07:20 is the safest bet, 3% chance of being 15+ min late; evening flights run 24–25%.

Safest bet that day WN 834 BUR 07:20 → SJC 08:35 · 3% chance 15+ min late · usually 92% on time Riskiest WN 840 BUR 17:55 → SJC 19:05 · 25% chance 15+ min late · usually 88% 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.


WN 834 Southwest Flight history →	BUR 07:20	SJC 08:35	3%	1%	1.6%	92%
WN 835 Southwest Flight history →	BUR 09:55	SJC 11:05	7%	2%	1.5%	86%
WN 836 Southwest Flight history →	BUR 12:20	SJC 13:30	16%	4%	1.2%	67%
WN 4883 Southwest Flight history →	BUR 15:15	SJC 16:30	19%	4%	1.2%	78%
WN 4884 Southwest Flight history →	BUR 20:15	SJC 21:30	24%	8%	1.0%	67%
WN 840 Southwest Flight history →	BUR 17:55	SJC 19:05	25%	6%	1.1%	88%worse than usual

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