Today: UA 1678 at 19:28 is the safest bet, 28% chance of being 15+ min late; the others run 49%.

Safest bet today UA 1678 DCA 19:28 → IAH 21:59 · 28% chance 15+ min late · usually 73% on time Riskiest OH 5411 DCA 20:43 → IAH 23:07 · 49% chance 15+ min late

Against a calm day 42% average chance a nonstop arrives 15+ min late; 36% for the same flights on a calm-weather day

Every nonstop today

12-month record →

Ranked by the chance of arriving 15+ minutes late, 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. 9 flights that already left today are not shown.


UA 1678 United Flight history →	DCA 19:28	IAH 21:59	28%	8%	0.4%	73%
AA 5222 American flown by PSA Flight history →	DCA 19:56	IAH 22:14	49%	18%	1.3%	36%
OH 5411 PSA	DCA 20:43	IAH 23:07	49%	15%	1.3%	no record

How these are worked out. Each flight’s odds are our forecast for that day; 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 4 (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