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

🇺🇸 N27722 - Boeing 737NG 724/W - United Airlines UAL2218/UA2218 (IAH-DCA-ORD) - 4.6 mi away @ 38900 ft, heading NNE at 591 mph. Spotted 19x before! [08:26:04 PM CDT] #A2C336 #N27722 #B737 #UNITED #UAL2218 #UA2218 #ADSB #ADSBbot