Yachting Monthly — November 2017

20 http://www.yachtingmonthly.com NOVEMBER 2017

How to unlock the

secrets of winds on

a weather shore

EXPERT ON BOARD

A weather shore may give shelter, but it’s not something

you should take for granted. Ken Endean explains why

W

e all know about lee shores.

Nasty places where wind

and sea thrash against the

land, so that prudent sailors

stay well to windward. An

ability to beat clear of a lee shore under

sail, in rough conditions, is an essential

safety factor in any yacht because

even supposedly reliable engines are

vulnerable to hazards such as fuel tank

bugs and fl oating crab pot lines.

Weather shores, where the wind blows

off the land, seem more enticing and

offer the prospect of fl at-water sailing

with an opportunity to visit sheltered

bays and coves. And yet, the air does not

always slide off the coast in a civilised

manner. The land interferes with the

wind, sometimes increasing its strength

rather than weakening it, often changing

its direction, and in some places these

effects can turn a supposedly sheltered

anchorage into a cauldron of howling

gusts. Conversely, a land mass may

encourage helpful inshore breezes on

days when the open sea is relatively

windless – useful propulsion for coastal

sailors who enjoy playing the shifts and

making the most of their canvas.

These local variations are unlikely to be

mentioned in any weather forecast, and

some of their causes are ignored or over-

simplifi ed in most sailing manuals. The

best way to understand the atmospheric

quirks is by spending time afl oat, by

careful observation, and by attempting

to visualise how the land is infl uencing

the air fl ow. In many ways, moving air

behaves in a similar manner to fl owing

water, as they are both fl uids, but the

air’s behaviour is also greatly infl uenced

by variations in temperature. A yacht

skipper is unlikely to have access to the

atmospheric temperature data that is

available to meteorologists but clouds,

mist and other phenomena often provide

visual clues, so it is helpful to know what

to look for.

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MAIN PHOTO: MIROSLAV VALASEK/ALAMY ALL PHOTOS KEN ENDEAN UNLESS STATED OTHERWISE