Gulf of Alaska tides swing wide under new moon as water cools

What's next

Expect the spring-tide effect to hold over the next few days while the moon stays new, so exchange and current will run stronger than average before easing back toward the following quarter phase. The predawn high-water windows, roughly 1:30 to 3 a.m. local, are worth building an early trip around if you want moving water; the morning low around 7 to 9 a.m. is the calmer bookend for working structure at a slower pace. Water temperature should keep sliding another degree or two over the coming week as days shorten, consistent with the drop already showing at both stations.

Plan around the tide swing more than the clock this week — a new-moon spring tide outweighs a typical weekday pattern for timing a trip.

Context

Upper-40s water and a strengthening new-moon tide in mid-October are on schedule for the Gulf of Alaska, which is moving out of its late-summer peak into the steeper fall cooldown that typically runs through November. Tidal ranges climb toward seasonal highs around new and full moons, so this week's wider swing is expected behavior for the calendar rather than anything unusual.