ON TIMEBOARD

DL 1237 on time

Delta Air Lines 1237: Sioux Falls to Atlanta at 5:20 a.m. (past 12 months)

On time
85%
365 flights · likely 81–88%
Cancelled
0.8%
of scheduled flights
Typical arrival
−12 min
median vs schedule
When late
+111 min
average delay
Similar flights
85%
DL, same route & hour

About 1 in 7 DL 1237 flights from Sioux Falls arrived 15+ minutes late, diverted or cancelled over the past year (15%); 0.8% were cancelled. The typical flight landed 12 minutes early.

DL 1237: FSD → ATL

Scheduled to leave Sioux Falls at 5:20 a.m. local time. Over the past year it arrived on time 85% of the time (365 flights), in line with other DL flights on the route at that hour (85%). Last seen in the data Aug 31, 2026.

Month by month

40%70%100%Sep 2025: 93% on time (30 flights)93SepOct 2025: 71% on time (31 flights)71OctNov 2025: 73% on time (30 flights)73NovDec 2025: 68% on time (31 flights)68DecJan 2026: 90% on time (31 flights)90JanFeb 2026: 93% on time (28 flights)93FebMar 2026: 77% on time (31 flights)77MarApr 2026: 93% on time (30 flights)93AprMay 2026: 94% on time (31 flights)94MayJun 2026: 83% on time (30 flights)83JunJul 2026: 97% on time (31 flights)97JulAug 2026: 87% on time (31 flights)87Aug

By day of week

DayFlightsOn time
Monday5383%
Tuesday5281%
Wednesday5288%
Thursday5290%
Friday5290%
Saturday5283%
Sunday5279%

Why it was late

Airline (crew, maintenance, ops) 68%Severe weather 14%Air traffic & airport (NAS) 11%Late inbound plane 7%

All flights FSD → ATL · Connecting off DL 1237? Check the risk

Questions

How often is DL 1237 from FSD to ATL late?

Delta Air Lines 1237 from Sioux Falls, SD to Atlanta, GA arrived 15 or more minutes late, was diverted or was cancelled on 15% of 365 scheduled flights between September 2025 and August 2026. 0.8% were cancelled.

Flight numbers change. Figures cover flights with this airline, number and route only. "Likely range" is the 95% interval for the true on-time rate given the number of flights. This is history, not live status: check Delta Air Lines for today's flight. Method.