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Note 262.0 BEAUFORT WIND FORCE CHART No replies
JOKUR::WHEELER "Ken" 124 lines 19-MAY-1988 15:05
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The Beaufort Scale of wind force is more than the mere
categorization of windspeeds. It is also a scale which relates
the wind force to the behaviour of the sea. The speed of the
wind can be estimated from the behaviour of the sea, or
visa-versa. The effects of the wind on land have been included
to help you assess the conditions before venturing out onto the
sea.
The scale is designed for the open sea so the effects ay vary in
enclosed waters or near land with an offshore wind. This is
particularly true of the wave heights which will be smaller but
steeper.
THE BEAUFORT SCALE OF WIND FORCE
-----+-------+-------------+------------------+----------+----------------
WIND | WIND | DESCRIPTION |EFFECTS ON THE SEA| PROBABLE | EFFECT ON LAND
FORCE| SPEED | | | WAVE |
|(KNOTS)| | | HEIGHT |
| | | | (METERS) |
| | | | |
| | | | |
0 | 0-1 | Calm |Sea like a mirror | 0 |Smoke rises
| | | | |vertically
| | | | |
| | | | |
1 | 1-3 | Light air |Ripples with the | 0.1 |Direction of
| | |appearance of | |wind shown by
| | |scales are formed,| |smoke but not
| | |but without foam | |by wind waves.
| | |foam crests. | |
| | | | |
| | | | |
2 | 4-6 | Light |Small wavelets, | 0.5 |Leaves rustle,
| | breeze |still short but | |wind vane moves
| | |more pronounced. | |with the wind.
| | |Crests have a | |
| | |glassy appearance | |
| | |and do not break. | |
| | | | |
3 | 7-10 | Gentle |Large wavelets. | 1.0 |Continual
| | breeze |Crests begin to | |Motion of
| | |break. Foam of | |Leaves and
| | |glassy appearance.| |small twigs.
| | |Perhaps scattered | |
| | |white horses. | |
| | | | |
4 | 11-16 | Moderate |Small waves, | 2.0 |Small branches
| | Breeze |becomming longer, | |move. Rasies dust
| | |fairly frequent | |and loose paper.
| | |white horses. | |
| | | | |
5 | 17-21 | Fresh |Moderate waves, | 3.0 |Small trees sway,
| | breeze |taking a more | |crest wavelets on
| | |prounounced long | |inland waters.
| | |form, many white | |
| | |horses are formed.| |
| | |Chance of some | |
| | |spray. | |
| | | | |
6 | 22-27 | Strong |Large waves begin | 4.0 |Large branches
| | breeze |to form, the white| |move, telegraph
| | |foam crests are | |whistle,
| | |more extensive. | |unbreallas used
| | |Probably some | |with difficulty
| | |spray | |
| | | | |
7 | 28-33 | Near Gale |Sea heaps up and | |Whole trees
| | |white foam from | |Sway, incon-
| | |breaking waves | |venient to walk
| | |begin to be blown | |against the wind.
| | |in streaks alonge | |
| | |along the | |
| | |direction of the | |
| | |wind | |
| | | | |
8 | 34-40 | Gale |Moderately high | |Breaks-twigs
| | |waves of greater | |off trees, wind
| | |length, edges of | |generally
| | |crests begin to | |impedes progress
| | |break into spin- | |
| | |drift. The foam | |
| | |is blown in well- | |
| | |marked streaks | |
| | | | |
9 | 41-47 | Strong |High waves. Dense | 7.0 |Slight struc-
| | gale |streaks of foam | |tural damage
| | |along the | |(eg. chimney
| | |direction of the | |pots and roof
| | |wind. Crests of | |slates blown
| | |waves begin to | |away.
| | |topple,tumble and | |
| | |roll over. Spray | |
| | |may affect | |
| | |visibility. | |
| | | | |
10 | 48-55 | Storm |Very high waves | 9.0 |Trees uprooted
| | |with loud over- | |considerable
| | |hanging crests. | |structural damage
| | |The resulting foam| |occurs
| | |in great patches | |
| | |blown in dense | |
| | |white streaks | |
| | |along the | |
| | |direction of the | |
| | |wind. The surface | |
| | |the sea takes on a| |
| | |white appearance. | |
| | |tumbling of the | |
| | |sea becomes heavy | |
| | |and shocklike. | |
| | |Visibility | |
| | |affected | |
-----+-------+-------------+------------------+----------+-----------------
|
| Whilst I agree wholeheartedly with the content of .-1 as a useful
indicator of Beaufort speed, I like the one I received from my charter
company in Greece last year much better :-
Force 0 Wind : Boring
Windsurfers practice rescue tactics and snoring
Dinghies paddle around
Yots stop for a swim
Force 1-2 Wind : Light Breeze
Winsurfers - paradise for novices, intermediates wake up and
experts continue sleeping
Dinghies - Idyllic sunbathing sail
Yots - debate whether to turn engine off
Force 3-4 Wind : Good Breeze
Windsurfers - Paradise for intermediates, novices topple like
nine-pins, experts wake up
Dinghies - Lots of activity, great fun!
Yots - Steady sailing, break out the Pimms
Force 5-6 Wind : Strong
Windsurfers - Experts paradise, Intermediates topple and beginners
sleep
Dinghies - Hectic for the experienced, others panic
Yots - Reef in and prop Pimms in the corner
Force 7+ Wind : Gales
Windsurfers - REAL experts change to a smaller sail, Posers
topple like nine-pins, spectators gather to watch
the fun.
Dinghies - Practice survival tactics in the bar
Yots - Cover Pimms to keep salt spray out
Happy Pimm'ing! Brian
|