North Pacific storm

45°55.9′N 160°42.5′W

Waves left about 6 Sep 08:46Z, ± 2 h

Placed by 8 buoys, whose own placements lie within 307 mi 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