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 4963 at 08:09 is the safest bet, 8% chance of being 15+ min late; evening flights run 30–31%.

Safest bet that day WN 4963 STL 08:09 → DCA 11:19 · 8% chance 15+ min late Riskiest WN 3732 STL 19:49 → DCA 22:58 · 31% chance 15+ min late

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 4963 Southwest	STL 08:09	DCA 11:19	8%	3%	0.8%	no record
YX 4678 Republic	STL 06:50	DCA 10:04	10%	4%	2.2%	no record
AA 4645 American flown by Republic Flight history →	STL 11:21	DCA 14:43	17%	6%	1.6%	80%
YX 4508 Republic	STL 13:24	DCA 16:46	20%	7%	1.6%	no record
WN 3522 Southwest	STL 13:20	DCA 16:30	23%	7%	0.8%	no record
AA 2030 American	STL 17:11	DCA 20:35	30%	13%	1.7%	no record
WN 3619 Southwest	STL 16:12	DCA 19:19	30%	10%	0.9%	no record
WN 3732 Southwest	STL 19:49	DCA 22:58	31%	10%	0.8%	no record

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