THE BEAUFORT SCALE

Long before the invention of mechanical or electronic wind meters, a British naval officer, Francis Beaufort, developed a method for describing wind strength based on the observation of wind related phenomena. This was the Beaufort Scale. It is still used in sailboat racing. The scale describes a whole range of wind and weather conditions from sleepy windless doldrums to gale force winds. The Beaufort wind force is factored into the Portsmouth handicap rating on any given race.

Beaufort Wind Scale

Miles Per Hour

Wind Condition

Phenomenon
Beaufort 1
1-3 mph
calm
water is mirror-like
Beaufort 2
4-7 mph
light breeze
ripples and scales on the water
Beaufort 3
8-12 mph
gentle breeze
small glassy waves
Beaufort 4
13-18 mph
moderate breeze
some waves, great sailing
Beaufort 5
19-24 mph 
fresh breeze
whitecaps
Beaufort 6
25-31 mph
strong breeze
sailing to windward is strenuous
Beaufort 7
32-38 mph
moderate gale
wind whistles in the shrouds
Beaufort 8
39-46 mph
fresh gale
difficult to walk, sailing impossible
Beaufort 9
47-54 mph
strong gale
huge waves, rolling seas
Beaufort 10
55-63 mph
whole gale
dangerous seas, structural damage
Beaufort 11
>64 mph
hurricane
spray fills the air, no visibility

Tornado Alley Sailing Club does not advise skippers to sail their boats during life-threatening atmospheric conflagrations. But if you choose to do so, we advise you to always wear a personal flotation device and, of course, have fun.