Bluegraph
SIMarineUS

Storms placed by their swell

North Pacific storm

32°31.8′N 164°24.2′W

Waves left about 24 Sep 22:53Z, ± 4 h

Placed by 4 buoys, whose own placements lie within 237 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