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Temperature

Beaufort Wind Scale
Force Wind
Knots
WMO
Description
Estimating Wind Speed
Effects At Sea Effects Near Land Effects On Land
0 Under 1 Calm Sea like a mirror Calm Calm; smoke rises vertically
1 1-3 Light Air Ripples with appearance of scales; no foam crests Small sailboat just has steerage way Smoke drift indicates wind direction; vanes do not move
2 4-6 Light Breeze Small wavelets; crests of glassy appearance; not breaking Wind fills the sails of small boats which then travel at about 1-2 knots Wind felt on face; leaves rustle; vanes begin to move
3 7-10 Gentle Breeze Large wavelets; crests begin to break, scattered whitecaps Sailboats begin to heel and travel at about 3-4 knots Leaves and small twigs in constant motion; light flags extended
4 11-16 Moderate Breeze Small waves 1-4 ft., becoming longer; numerous whitecaps Good working breeze, sailboats carry all sail with good heel Dust, leaves, and loose paper raised up; small branches move.
5 17-21 Fresh Breeze Moderate waves 4-8 ft taking longer form; many whitecaps; some spray Sailboats shorten sail Small trees in leaf begin to sway
6 22-27 Strong Breeze Larger waves 8-13 ft forming white caps everywhere; more spray Sailboats have double reefed mainsails Larger branches of trees in motion; whistling heard in wires
7 28-33 Near Gale Sea heaps up, waves 13-20 ft; white foam from breaking waves begins to be blon in streaks Boats remain in harbor; those at sea heave-to Whole trees in motion; resistance felt in walking against wind
8 34-40 Gale Moderately high (13-20 ft) waves of greater length; edges of crests begin to break into spindrift; foam is blown in wellmarked streaks Boats remain in harbor; those at sea heave-to Whole trees in motion; resistance felt inwalking against wind
9 41-47 Strong Gale High waves (20 ft); sea begins to roll; dense streaks of foam; spray may reduce visibility   Slight structural damage occure; slate blows from roofs
10 48-55 Storm Very high waves (20-30 ft) with overhanging crests;sea takes a white apperance as foam is blown in very dense streaks; rolling is heavy and visibility is reduced   Seldom experienced on land; trees broken or uprooted; considerable structural damage occurs
11 56-63 Violent Storm Exceptionally high (30-45 ft) waves; sea covered with white foam patches; visibility still more reduced    
12 64 -up Hurricane Air filled with foam; waves over 45 ft; sea completely white with driving spray; visibility greatly reduced    

Note: The Beaufort Wind Scale goes to Force 12. It is only academic at this level. All sailors by this time are in port, wish they were, being beaten up, or sinking.


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The information presented in this sailing checklist is that which has been collected over years of boating experience. The information presented here, including the medical information, is not intended as professional advice; rather, it is a starting point for your own thinking and organization.
Copyright © 1996, Chuck and Chris Hanson

Created: 12/24/95
Last Updated: 2/2/96 11:39:52 AM


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