North Atlantic storm

43°50.5′N 038°18.0′W

Waves left about 26 Sep 20:11Z, ± 5 h

Placed by 2 buoys, whose own placements lie within 308 mi 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