Tracked live by the FAA, but its flight plan was first seen after takeoff, so we don't know the scheduled time and can't say whether it's late.

SOUTHWEST · FLIGHT WN 2099 LANDED 8:51 PM CT, ~5 MIN LATE · SCHEDULED TIME UNKNOWN

WN 2099 · MSY → STL

took off 7:27 PM CT · landed 8:51 PM CT (scheduled time unknown)
Forecast issued Fri 10:00 PM ET · 2h after departure

Odds over time

Arrive at STL more than 15 minutes late?
40% chance · ±1 pts – · 24h
HOW SURE WE ARE Very high. The odds now come almost entirely from live conditions.
LIVE IN THE AIR 0% 15% 30% 45% 60% 1h Departs Lands