North Pacific storm

43°22.3′N 142°11.5′W

Waves left about 26 Sep 03:43Z, ± 3 h

Placed by 2 buoys, whose own placements lie within 119 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