North Pacific storm

49°51.7′N 164°12.4′W

Waves left about 25 Sep 11:59Z, ± 1 h

Placed by 12 buoys, whose own placements lie within 323 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