WN 209 then UA 248 at Denver
St Louis → Denver → Omaha
Timetable, Denver time
18:50WN 209 from St Louis at the gate
17:59UA 248 to Omaha leaves the gate
23 h 09 apart on the timetable, overnight
UA 248 leaves 23 h 09 after WN 209 arrives on the timetable: more than half a day, so not a connection we count.