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

🇺🇸 N8524Z - Boeing 737NG 800/W - Southwest Airlines SWA18/WN18 (HOU-DAL-MDW) - 4.8 mi away @ 40550 ft, heading NNE at 534 mph. Spotted 73x before! [02:08:16 PM CDT] #ABB1C2 #N8524Z #B738 #SOUTHWEST #SWA18 #WN18 #ADSB #ADSBbot