synoptic wave chart

synoptic wave chart

[sə′näp·tik ′wāv ‚chärt]
(oceanography)
A chart of an ocean area on which is plotted synoptic wave reports from vessels, along with computed wave heights for areas where reports are lacking; atmospheric fronts, highs, and lows are also shown; isolines of wave height and the boundaries of areas having the same dominant wave direction are drawn.