AS21 New YorkJFK · 07:25 SeattleSEA · 10:34
AS21 by Alaska Airlines flies from New York (JFK) to Seattle (SEA) for the Tue, Sep 8 departure.
departs JFK · on schedule
board checked 8m ago · checking again in 45s
Where the minutes go
last 6 operations · gate push → arrivalThe bar is how late it left the gate; the ring is where it actually arrived. Board clocks, not estimates.
The last 30 days
arrival outcome per operation0 cancelled · 6 operations tracked
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at JFK and SEA are near their clear-air norm right now, so this reflects the route's recent baseline rather than a weather penalty. For this route and airline, under conditions like today's, over the last 90 days.
Pro Flight Search tracking, 90 days · the weather × delay correlation study → · live weather risk by airport →
When it flies
scheduled departuresEach mark is a scheduled departure at its origin-local time. Today is highlighted.
Other New York to Seattle flights today
same route · Alaska AirlinesIf AS21 is cancelled, these are the other Alaska Airlines nonstop flights from New York to Seattle on the same day, with scheduled departure times in JFK local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How AS21 actually runs
Pro Flight Search has tracked every published board update for AS21 across the JFK and SEA boards: schedule changes, gate pushes and actual clocks. Usually departs ~5 min early. Based on 6 confirmed departures · 5/6 within 15 min of schedule.
The verdict above is that record speaking, so it reflects how AS21 operates rather than what the timetable promises. Numbers refresh as new flights operate.
How this operation is measured
Board log
scheduled → actual, per operationBoard clocks recorded as JFK and SEA published them.
Planning around AS21? Will a delayed flight be cancelled? · Do planes make up time in the air? · How we measure
Journalists, bloggers, and researchers may cite this page with attribution and a link to Pro Flight Search.
Pro Flight Search — AS21 New York to Seattle on-time performance, measured from the JFK and SEA airport boards.
https://proflightsearch.com/flight/AS21
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