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 1519 at 07:59 is the safest bet, 8% chance of being 15+ min late; evening flights run 27–33%.

Safest bet that day WN 1519 DCA 07:59 → STL 09:25 · 8% chance 15+ min late · usually 78% on time Riskiest WN 398 DCA 18:49 → STL 20:17 · 33% 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 1519 Southwest Flight history →	DCA 07:59	STL 09:25	8%	2%	0.7%	78%
AA 4645 American flown by Republic Flight history →	DCA 08:41	STL 10:39	12%	3%	1.2%	85%
YX 4508 Republic	DCA 11:22	STL 13:04	15%	4%	1.1%	no record
WN 1521 Southwest	DCA 12:01	STL 13:28	21%	4%	0.7%	no record
YX 4536 Republic	DCA 18:53	STL 20:37	27%	8%	1.7%	no record
AA 2030 American	DCA 14:33	STL 16:12	28%	9%	0.9%	no record
WN 1522 Southwest	DCA 15:26	STL 16:54	28%	6%	0.8%	no record
WN 398 Southwest	DCA 18:49	STL 20:17	33%	8%	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