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 266 LANDED 2:18 AM CT, ~10 MIN LATE · SCHEDULED TIME UNKNOWN
Yesterday

WN 266 · PHL → DAL

took off 12:21 AM ET · landed 2:18 AM CT (scheduled time unknown)
Forecast issued Sat 11:00 PM ET · 23h after departure

Odds over time

Arrive at DAL more than 15 minutes late?
9% chance · ±0 pts −28 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% 2h Departs Lands