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 1758 LANDED 6:07 PM ET, ~13 MIN LATE · SCHEDULED TIME UNKNOWN

WN 1758 · MDW → PHL

took off 3:33 PM CT · landed 6:07 PM ET (scheduled time unknown)
Forecast issued Tue 10:00 PM ET · 6h after departure

Odds over time

Arrive at PHL more than 15 minutes late?
35% chance · ±0 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% 13h 6h Departs Lands