North Pacific storm

39°46.1′N 161°41.8′E

Waves left about 22 Oct 16:00Z, ± 4 h

Placed by 4 buoys, whose own placements lie within 286 nmi of it

Its swell is still arriving: last measured at 51212 (Barbers Point, Kalaeloa, HI (238)) on 29 Oct 04:34Z.

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