Why is the swell greyed out in the forecast?
When you see a swell greyed out, it means the period is so low that it won’t produce surfable waves. Very short-period swells don’t create waves of interest to surfers, so we show them in grey to avoid confusion.
Greyed out swell may appear as primary well if slightly-higher-period swell is coming from an indirect angle.
Does a non-grey swell always mean surfable waves?
No. Even if a swell isn’t greyed out, it doesn’t guarantee surfable conditions. We grey out a swell component only when it has no chance of producing rideable surf at any spot, in any direction, no matter how exposed. Other visible swells may still be too small, inconsistent, or unfavorable for good waves.
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