The combined waveheight is contoured every meter with supplementary
dashed lines of 0.5 meter. In the adjacent seas, prevailing wave direction and period are
plotted on the point every about 250km with an open arrow and a numeral. Wind direction
and speed are plotted with a wind arrow on the same point. For the 26 selected coastal
grid points from A to Z around Japan (see the table in page 10), coastal wave and wind
data are tabulated in the chart. Measured significant waves with 11 coastal wave recorders
are also shown in another table (see the table and figure in page 10).