North Pacific storm

25°54.6′N 122°47.5′W

Waves left about 3 Sep 08:42Z, ± 4 h

Placed by 2 buoys, whose own placements lie within 341 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