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 4661 LANDED 9:37 PM MT, ~7 MIN LATE · SCHEDULED TIME UNKNOWN

WN 4661 · PHX → DEN

took off 7:21 PM MT · landed 9:37 PM MT (scheduled time unknown)
Forecast issued Tue 10:00 PM ET · 0h before departure

Odds over time

Arrive at DEN more than 15 minutes late?
53% chance · ±1 pts +1 pt · 24h
HOW SURE WE ARE Very high. The odds now come almost entirely from live conditions.
WEATHER FORECASTS LIVE IN THE AIR 0% 20% 40% 60% 80% 1.1d 12h 6h Now Departs Lands