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

🇺🇸 N920NN - Boeing 737NG 823/W - American Airlines AAL1077/AA1077, Cozumel (CZM) to Chicago O'Hare (ORD) - 4.7 mi away @ 39975 ft, heading NNE at 563 mph. Spotted 41x before. [06:38:22 PM CST] #ACBF63 #N920NN #B738 #AMERICAN #AAL1077 #AA1077 #ADSB #ADSBbot