266 seamanship secrets
divided crests meet each other on the island’s lee side, a cross swell develops. Many
a mariner has spent an uncomfortable night at anchor, rolling and hobbyhorsing
in a cross swell. If you are sailing in a trade wind region, study the chart and look
for irregularly shaped islands with indentations or coves on their lee sides, or fi nd
islands with steeper bottom contours on one side than the other. Such islands off er
prospects of secure lee-side anchorages.
Waves wrap around the sides of this roundish island, then meet on the island’s back side to
form a cross swell.
Avoid anchoring in the cone of turbulent water behind the points of islands or breakwaters.
Th e center of the lee side of this island will have much calmer water because no cross swell
exists, unlike the island in the previous illustration.