Sunday, October 11 · typical odds for a Sunday (too early for a weather forecast) · issued Mon 12:00 AM ET · 3 nonstops

Sun, Oct 11: WN 4128 at 05:45 is the safest bet, 4% chance of being 15+ min late; the others run 12–27%.

Safest bet that day WN 4128 STL 05:45 → TPA 09:16 · 4% chance 15+ min late Riskiest WN 4130 STL 19:55 → TPA 23:26 · 27% chance 15+ min late

Every nonstop on Sun, Oct 11

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 4128 Southwest	STL 05:45	TPA 09:16	4%	1%	1.0%	no record
WN 3100 Southwest	STL 10:15	TPA 13:47	12%	5%	1.4%	no record
WN 4130 Southwest	STL 19:55	TPA 23:26	27%	11%	0.7%	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 Sun, Oct 11 (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