Gulf of Alaska storm

50°53.3′N 154°49.5′W

Waves left about 26 Sep 00:05Z, ± 2 h

Placed by 4 buoys, whose own placements lie within 177 nmi of it

Each buoy places the storm from how its swell's period shortened as it arrived: the longest waves travel fastest. Fronts are drawn at deep-water group speeds along great circles, and stop at land. How it is worked out