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

🇺🇸 N14528 - AIRBUS A321-271NX - United Airlines UAL1925/UA1925 (SBP-DEN-DCA) - 4.5 mi away @ 37175 ft, heading E at 528 mph. Spotted once before! [12:27:05 PM CDT] #A0B802 #N14528 #A21N #UNITED #UAL1925 #UA1925 #ADSB #ADSBbot