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STATION—
OBS TIME (UTC)—
SWH (Hmo)—
PEAK PERIOD—
PERIOD RANGE SHOWN—
FRAME—
Rings: wave period (s), fixed at 25–4s outer→inner (0.04–0.25 Hz).
Angle: compass direction waves come FROM, in degrees clockwise from north (000°=N, 090°=E, 180°=S, 270°=W).
Color: spectral density (m²/Hz/rad), rainbow scale low→high.
Center arrow: dominant wave direction at peak period.