Monday, October 12 · typical odds for a Monday (too early for a weather forecast) · issued Tue 12:00 AM ET · 8 nonstops

Mon, Oct 12: WN 2371 at 05:29 is the safest bet, 4% chance of being 15+ min late; evening flights run 17–24%.

Safest bet that day WN 2371 ONT 05:29 → LAS 06:40 · 4% chance 15+ min late Riskiest F9 4758 ONT 14:17 → LAS 15:37 · 30% chance 15+ min late · usually 70% on time

Every nonstop on Mon, Oct 12

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 2371 Southwest	ONT 05:29	LAS 06:40	4%	1%	0.6%	no record
WN 442 Southwest	ONT 08:39	LAS 09:50	10%	1%	0.6%	no record
WN 4908 Southwest	ONT 21:29	LAS 22:40	17%	4%	0.6%	no record
F9 2232 Frontier Flight history →	ONT 07:47	LAS 09:07	18%	5%	0.9%	84%
WN 2424 Southwest	ONT 17:14	LAS 18:25	24%	5%	0.6%	no record
WN 3268 Southwest	ONT 13:29	LAS 14:40	24%	4%	0.6%	no record
F9 4206 Frontier Flight history →	ONT 20:16	LAS 21:36	24%	7%	1.1%	73%
F9 4758 Frontier Flight history →	ONT 14:17	LAS 15:37	30%	11%	0.9%	70%

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 Mon, Oct 12 (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