WN 191 then Y4 2410 at San Francisco
St Louis → San Francisco → Denver
Timetable, San Francisco time
12:25WN 191 from St Louis at the gate
12:20Y4 2410 to Denver leaves the gatealso F9 3436
23 h 55 apart on the timetable, overnight
Y4 2410 leaves 23 h 55 after WN 191 arrives on the timetable: more than half a day, so not a connection we count.