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

🇺🇸 N221WN - Boeing 737NG 7H4/W - Southwest Airlines SWA1045/WN1045, St Louis Lambert (STL) to Denver (DEN) - 3.6 mi away @ 16825 ft, heading WNW at 425 mph. Spotted 35x before! [10:42:44 AM CST] #A1E6B9 #N221WN #B737 #SOUTHWEST #SWA1045 #WN1045 #Departure #ADSB #ADSBbot