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

🇺🇸 N664FR - AIRBUS S A S A321-271NX - Frontier Airlines FFT1362/F91362, Denver (DEN) to Charlotte/Douglas (CLT) - 4.4 mi away @ 37125 ft, heading ESE at 560 mph. Spotted for first time! [02:27:47 PM CDT] #A8C3A2 #N664FR #A21N #FRONTIER_FLIGHT #FFT1362 #F91362 #ADSB #ADSBbot