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

🇺🇸 N8743K - Boeing 737MAX 8 - Southwest Airlines SWA218/WN218, Chicago Midway (MDW) to Cancun (CUN) - 4.5 mi away @ 37425 ft, heading SSW at 456 mph. Spotted 51x before! [01:26:18 PM CDT] #AC07FD #N8743K #B38M #SOUTHWEST #SWA218 #WN218 #ADSB #ADSBbot