Saturday, October 10 · typical odds for a Saturday (too early for a weather forecast) · issued Sun 8:00 PM ET · 4 nonstops

Sat, Oct 10 looks like a normal day here: all 4 nonstops are 6–14% likely to arrive 15+ min late.

Safest bet that day WN 1519 DCA 08:17 → STL 09:50 · 6% chance 15+ min late · usually 78% on time Riskiest WN 494 DCA 18:42 → STL 20:15 · 14% chance 15+ min late

Every nonstop on Sat, Oct 10

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 08:17	STL 09:50	6%	1%	0.6%	78%
YX 4690 Republic	DCA 16:19	STL 17:48	10%	3%	0.8%	no record
WN 1521 Southwest	DCA 12:37	STL 14:10	10%	2%	0.6%	no record
WN 494 Southwest	DCA 18:42	STL 20:15	14%	3%	0.6%	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 Sat, Oct 10 (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