Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 6 nonstops

Fri, Oct 9: WN 4976 at 06:00 is the safest bet, 4% chance of being 15+ min late; evening flights run 23–32%.

Safest bet that day WN 4976 MDW 06:00 → DCA 08:45 · 4% chance 15+ min late · usually 95% on time Riskiest WN 1157 MDW 17:05 → DCA 19:55 · 32% chance 15+ min late · usually 37% 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 4976 Southwest Flight history →	MDW 06:00	DCA 08:45	4%	1%	0.7%	95%
WN 2569 Southwest Flight history →	MDW 08:15	DCA 11:10	7%	2%	0.6%	91%
WN 2761 Southwest Flight history →	MDW 12:45	DCA 15:35	18%	5%	0.7%	75%
WN 1294 Southwest Flight history →	MDW 11:15	DCA 14:00	21%	5%	0.6%	56%
WN 1172 Southwest Flight history →	MDW 20:10	DCA 23:05	23%	8%	0.7%	31%
WN 1157 Southwest Flight history →	MDW 17:05	DCA 19:55	32%	10%	0.7%	37%

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