AS357 SeattleSEA · 07:40 BostonBOS · 16:24
AS357 by Alaska Airlines flies from Seattle (SEA) to Boston (BOS).
scheduled from SEA
Where the minutes go
last 4 operations · gate push → arrivalThe bar is how late it left the gate; the ring is where it actually arrived. Board clocks, not estimates.
The route today
live boardsWeather lens
Delay & cancellation outlook for this flight
Measured, 90-day sampleConditions at SEA and BOS 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 Seattle to Boston flights today
same route · Alaska AirlinesIf AS357 is cancelled, these are the other Alaska Airlines nonstop flights from Seattle to Boston on the same day, with scheduled departure times in SEA local time. Most flights posting a delay still operate — rebooking usually only beats a very large posted delay. Every airline on this route →
How AS357 actually runs
Pro Flight Search has tracked every published board update for AS357 across the SEA and BOS boards: schedule changes, gate pushes and actual clocks. Early read — pattern not clear yet. Only 3 completed legs so far: landed +45 min. Not enough to call it.
The verdict above is that record speaking, so it reflects how AS357 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 SEA and BOS published them.
Planning around AS357? 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 — AS357 Seattle to Boston on-time performance, measured from the SEA and BOS airport boards.
https://proflightsearch.com/flight/AS357
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