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 4506 LANDED 1:53 AM CT, ~4 MIN LATE · SCHEDULED TIME UNKNOWN
Today

WN 4506 · MDW → MEM

took off 12:42 AM CT · landed 1:53 AM CT (scheduled time unknown)
Forecast issued Tue 7:00 PM ET · 17h after departure

Odds over time

Arrive at MEM more than 15 minutes late?
11% chance · ±0 pts −26 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% 3h Departs Lands