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

Fri, Oct 9: WN 4933 at 06:15 is the safest bet, 4% chance of being 15+ min late; evening flights run 25–26%.

Safest bet that day WN 4933 SJC 06:15 → LGB 07:35 · 4% chance 15+ min late · usually 98% on time Riskiest WN 3684 SJC 17:05 → LGB 18:25 · 26% chance 15+ min late · usually 64% 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 4933 Southwest Flight history →	SJC 06:15	LGB 07:35	4%	2%	0.5%	98%
WN 4958 Southwest Flight history →	SJC 09:55	LGB 11:15	8%	4%	0.5%	92%
WN 4907 Southwest Flight history →	SJC 19:50	LGB 21:10	25%	9%	0.5%	79%
WN 3684 Southwest Flight history →	SJC 17:05	LGB 18:25	26%	9%	0.5%	64%

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