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 2135 LANDED 8:58 PM MT, ~3 MIN EARLY · SCHEDULED TIME UNKNOWN
Yesterday

WN 2135 · DEN → SLC

took off 7:58 PM MT · landed 8:58 PM MT (scheduled time unknown)
Forecast issued Tue 10:00 PM ET · 0h before departure

Odds over time

Arrive at SLC more than 15 minutes late?
33% chance · ±0 pts −9 pts · 24h
HOW SURE WE ARE Very high. The odds now come almost entirely from live conditions.
WEATHER FORECASTS LIVE IN THE AIR 0% 15% 30% 45% 60% 1.0d 12h 6h Departs Lands