Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 22 nonstops

Fri, Oct 9: WN 3737 at 05:35 is the safest bet, 2% chance of being 15+ min late; evening flights run 18–34%.

Safest bet that day WN 3737 SLC 05:35 → DEN 07:00 · 2% chance 15+ min late · usually 98% on time Riskiest WN 3740 SLC 16:50 → DEN 18:20 · 34% chance 15+ min late · usually 28% 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 3737 Southwest Flight history →	SLC 05:35	DEN 07:00	2%	1%	0.6%	98%
UA 5683 United flown by SkyWest Flight history →	SLC 05:15	DEN 06:54	4%	2%	0.5%	95%
WN 3738 Southwest Flight history →	SLC 07:25	DEN 08:55	7%	2%	0.5%	95%
UA 1232 United Flight history →	SLC 07:00	DEN 08:42	7%	2%	0.5%	95%
F9 3220 Frontier Flight history →	SLC 06:05	DEN 07:43	8%	3%	0.8%	84%
UA 5642 United flown by SkyWest Flight history →	SLC 08:30	DEN 10:27	8%	3%	0.5%	81%
UA 4720 United flown by SkyWest Flight history →	SLC 13:05	DEN 14:51	9%	4%	0.5%	92%
DL 1317 Delta Flight history →	SLC 07:45	DEN 09:12	9%	2%	0.5%	95%
UA 2004 United Flight history →	SLC 10:39	DEN 12:24	12%	4%	0.5%	92%
WN 1478 Southwest Flight history →	SLC 12:20	DEN 13:50	13%	4%	0.5%	85%
DL 1553 Delta Flight history →	SLC 10:15	DEN 11:47	13%	3%	0.5%	84%
DL 1623 Delta Flight history →	SLC 13:20	DEN 14:53	16%	4%	0.5%	85%
WN 3739 Southwest Flight history →	SLC 10:40	DEN 12:05	18%	3%	0.6%	51%
DL 1667 Delta Flight history →	SLC 21:05	DEN 22:40	18%	5%	0.5%	79%
F9 3862 Frontier Flight history →	SLC 08:16	DEN 10:01	20%	5%	0.8%	81%
UA 1662 United Flight history →	SLC 14:28	DEN 16:11	22%	6%	0.5%	79%
WN 3741 Southwest Flight history →	SLC 19:35	DEN 21:05	23%	7%	0.5%	65%
WN 4851 Southwest Flight history →	SLC 21:40	DEN 23:10	24%	6%	0.5%	58%
UA 1910 United Flight history →	SLC 17:57	DEN 19:40	25%	7%	0.5%	70%
DL 1586 Delta Flight history →	SLC 18:30	DEN 20:01	26%	6%	0.5%	71%
F9 3982 Frontier Flight history →	SLC 15:41	DEN 17:21	28%	11%	0.8%	78%
WN 3740 Southwest Flight history →	SLC 16:50	DEN 18:20	34%	8%	0.5%	28%

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