Friday, October 9 · typical odds for a Friday (too early for a weather forecast) · issued Sun 4:00 PM ET · 5 nonstops

Fri, Oct 9 looks like a normal day here: all 4 nonstops are 7–13% likely to arrive 15+ min late.

Safest bet that day DL 1255 MDT 06:04 → ATL 08:02 · 7% chance 15+ min late · usually 91% on time Riskiest DL 2857 MDT 18:22 → ATL 20:35 · 13% chance 15+ min late · usually 83% 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. Dimmed: airlines we don’t forecast yet, shown with their 12-month record if they usually fly that weekday.


DL 1255 Delta Flight history →	MDT 06:04	ATL 08:02	7%	3%	0.8%	91%
DL 1248 Delta Flight history →	MDT 11:41	ATL 13:42	8%	3%	0.8%	86%
DL 2517 Delta Flight history →	MDT 14:57	ATL 16:58	13%	4%	0.8%	47%
DL 2857 Delta Flight history →	MDT 18:22	ATL 20:35	13%	4%	0.7%	83%
DL 4717 Delta flown by Endeavor no forecast: 12-month record	MDT 14:00	ATL 16:08	19%	15%	0.0%	81%

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