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

🇺🇸 N819NV - BOEING 737 MAX 8 - ALLEGIANT AIR LLC AAY488/G4488, Fort Lauderdale/Hollywood (FLL) to Des Moines (DSM) - 5.1 mi away @ 39875 ft, heading NW at 506 mph. Spotted for first time! [08:57:11 AM CDT] #AB2C0B #N819NV #B38M #AAY488 #G4488 #ADSB #ADSBbot