North Atlantic storm

38°17.3′N 045°29.3′W

Waves left about 23 Sep 18:24Z, ± 4 h

Placed by 3 buoys, whose own placements lie within 241 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