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.

REPUBLIC · FLIGHT YX 4727 LANDED 5:12 PM CT, ~6 MIN LATE · SCHEDULED TIME UNKNOWN
Today

YX 4727 · BOS → STL

took off 3:51 PM ET · landed 5:12 PM CT (scheduled time unknown)
Forecast issued Tue 4:00 PM ET · 0h before departure

Odds over time

Arrive at STL more than 15 minutes late?
33% chance · ±1 pts +10 pts · 24h
HOW SURE WE ARE Very high. The odds now come almost entirely from live conditions.
WEATHER FORECASTS LIVE IN THE AIR 0% 10% 20% 30% 40% 20h 12h 6h Departs Lands