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

🇺🇸 N321NB - Airbus A319 114 - Delta Air Lines DAL1633/DL1633, Detroit Metro Wayne County (DTW) to George Bush Intcntl/Houston (IAH) - 4.2 mi away @ 35550 ft, heading WSW at 530 mph. Spotted 18x before! [09:07:46 PM CDT] #A37335 #N321NB #A319 #DELTA #DAL1633 #DL1633 #ADSB #ADSBbot