Beaufort Scale – a Guide for Canoeing and Kayaking
Before going out on the water, canoe and kayak coaches and group leaders often need to plan taking into consideration the weather forecast they have obtained. So it can be really useful to be able to judge what water conditions to expect based on a given wind forecast. The version of the Beaufort Scale below helps you do this. Simply find the wind speed expected from the forecast and look across to how this is likely to affect the water. This is particularly relevent for sea kayakers or those travelling on exposed open water.
BEAUFORT SCALE: Specifications and equivalent speeds for use at sea
FORCE EQUIVALENT SPEED DESCRIPTION SPECIFICATIONS FOR USE AT SEA
10 m above ground
miles/hour knots
0 0-1 0-1 Calm Sea like a mirror
1 1-3 1-3 Light air Ripples with the appearance of
scales are formed, but without
foam crests.
2 4-7 4-6 Light Breeze Small wavelets, still short,
but more pronounced. Crests
have a glassy appearance and
do not break.
3 8-12 7-10 Gentle Breeze Large wavelets. Crests begin
to break. Foam of glassy
appearance. Perhaps scattered
white horses.
4 13-18 11-16 Moderate Breeze Small waves, becoming larger;
fairly frequent white horses.
5 19-24 17-21 Fresh Breeze Moderate waves, taking a more
pronounced long form; many
white horses are formed.
Chance of some spray.
6 25-31 22-27 Strong Breeze Large waves begin to form; the
white foam crests are more
extensive everywhere.
Probably some spray.
7 32-38 28-33 Near Gale Sea heaps up and white foam
from breaking waves begins to
be blown in streaks along the
direction of the wind.
8 39-46 34-40 Gale Moderately high waves of greater
length; edges of crests begin to
breakinto spindrift. The foam is
blown in well-marked streaks
along the direction of the wind.
9 47-54 41-47 Severe Gale High waves. Dense streaks of
foam along the direction of the
wind. Crests of waves begin to
topple, tumble and roll over.
Spray may affect visibility.
10 55-63 48-55 Storm Very high waves with long over-
hanging crests. The resulting
foam, in great patches, is blown
in dense white streaks along the
direction of the wind. On the
whole the surface of the sea
takes on a white appearance.
The 'tumbling' of the sea becomes
heavy and shock-like. Visibility
affected.
11 64-72 56-63 Violent Storm Exceptionally high waves (small
and medium-size ships might be for
a time lost to view behind the
waves). The sea is completely
covered with long white patches
of foam lying along the direction
of the wind. Everywhere the edges
of the wave crests are blown into
froth. Visibility affected.
12 73-83 64-71 Hurricane The air is filled with foam and
spray. Sea completely white with
driving spray; visibility very
seriously affected.
You can learn how to understand the connection between water conditions and wind speed on our courses. This is covered within the BCU star tests and personal skills courses – so contact Kim for more information.
