Beaufort Scale

Description Wind Speed
Knots
Wind Speed
Km
Force Land Water
Calm 0 - 1 0 1 0 Smoke rises
vertically
Water is like a mirror. Cannot sail.
Light Air 1 - 3 1 - 5 1 Smoke indicates direction. Not enough wind for vanes Small ripples on water. Enough wind for a light Spinnaker
Light Breeze 4 - 6 6 - 11 2 Wind felt on face. Tree leaves start moving. Vanes now indicate direction. Small wavelets. Wind now fills sail.
Gentle Breeze 7 - 10 12 - 19 3 Small flags are extended. Leaves move constantly. Large wavelets. Sailboats start to heel.
Moderate Breeze 11 - 16 20 - 28 4 Dust is raised by wind. Small branches start bending. Good working breeze. Saiboats at hull speed, full sail.
Fresh Breeze 17 - 21 29 - 38 5 Small trees are reacting to wind. Numerous whitecaps. Time to shorten sails.
Strong Breeze 22 - 27 39 - 49 6 Wind now whistles. Most branches in trees moving. Whitecaps eveywhere. Sailboats start to head ashore.
Near Gale 28 ­ 33 50 - 61 7 Whole trees now move. Much bigger waves. Sailboats remain at harbour.
Gale 34 - 40 62 - 74 8 Small branches are starting to break. Walking in now hard. Foam in well marked streaks. All boats now head in.
Strong Gale 41 - 47 75 - 88 9 Buildings are starting to show small damage. Low visibility due to spray.
Storm 48 - 55 89 - 102 10 Dangerous Situation High seas over 8 metres
Violent Storm 56 - 63 103 - 117 11 Dangerous situation High seas over 10 metres
Hurricane Over 63 Over 117 12 Dangerous situation High seas over 14 metres

Weather Page

Saffir-Simpson Hurricane Scale - information about storm categories.

Information originally posted at Pat's BOATING IN CANADA

"If one does not know to which port one is sailing, no wind is favorable." - Seneca

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