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.

ALASKA · FLIGHT AS 306 IN THE AIR (OFF 10:41 PM ET, ETA 1:20 AM PT) · SCHEDULED TIME UNKNOWN
Yesterday

AS 306 · BOS → SEA

took off 10:41 PM ET · expected to land 1:20 AM PT (scheduled time unknown)
Forecast issued Tue 10:00 PM ET · 1h before departure

Odds over time

Arrive at SEA more than 15 minutes late?
41% chance · ±0 pts −3 pts · 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