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.

DELTA · FLIGHT DL 257 LANDED 4:44 PM ET, ~10 MIN LATE · SCHEDULED TIME UNKNOWN
Yesterday

DL 257 · AMS → BOS

took off 3:21 PM CEST · landed 4:44 PM ET (scheduled time unknown)
Forecast issued Tue 7:00 PM ET · 10h after departure

Odds over time

Arrive at BOS more than 15 minutes late?
18% chance · ±0 pts −14 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% 18h 12h 6h Departs Lands