Although observations of microseisms excited by ocean swells were firmly established in the 1940s, the source locations remain difficult to track. Delineation of the source locations and energy partition of the seismic wave components are key to understanding the excitation mechanisms. Using a seismic array in Japan, we observed bothPand S wave microseisms excited by a severe distant storm in the Atlantic Ocean. Although nonlinear forcing of an ocean swell with a one-dimensional Earth model can explainPwaves and vertically polarized S waves (SVwaves), it cannot explain horizontally polarizedSwaves (SHwaves). The precise source locations may provide a new catalog for exploring Earth's interior.