Map of the St. Louis area showing the position and track of the aircraft described in the post.

🇺🇸 N156SY - Embraer EMB-175 LR - United Express SKW5985/OO5985, Denver (DEN) to Birmingham-Shuttlesworth (BHM) - 4.0 mi away @ 33675 ft, heading SSE at 598 mph. Spotted 20x before! [01:35:07 PM CDT] #A0E220 #N156SY #E75L #SKYWEST #SKW5985 #OO5985 #autopilot #ADSB #ADSBbot