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

🇺🇸 N27239 - Boeing 737NG 824/W - United Airlines UAL1727/UA1727, Buffalo Niagara (BUF) to Denver (DEN) - 4.6 mi away @ 36150 ft, heading WSW at 540 mph. Spotted 8x before! [08:53:21 AM CDT] #A2B0CD #N27239 #B738 #UNITED #UAL1727 #UA1727 #ADSB #ADSBbot