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

🇺🇸 N77598 - BOEING 737 MAX 9 - United Airlines UAL2031/UA2031, San Diego (SAN) to Washington Dulles (IAD) - 4.4 mi away @ 37000 ft, heading E at 650 mph. Spotted 4x before. [05:50:59 PM CST] #AA7F4E #N77598 #B39M #UNITED #UAL2031 #UA2031 #ADSB #ADSBbot