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.

SUN COUNTRY · FLIGHT SY 3021 SCHEDULED · SCHEDULED TIME UNKNOWN
Today

SY 3021 · CVG → STL

departs 4:14 PM ET · arrives 4:07 PM CT
Your aircraft is N8059A (B738), coming in as SY 3004 from PHX: landed 7:14 AM ET.
Forecast issued Sat 1:00 PM ET · 3h before departure

Odds over time

Arrive at STL more than 15 minutes late?
30% chance · ±0 pts – · 24h
HOW SURE WE ARE High. The odds now come mostly from live FAA and airport data.
LIVE IN THE AIR 0% 10% 20% 30% 40% Now Departs Lands