FIGURE9 How to read wind symbols on a weather map
The small tail indicates the speed of the wind.
Direction
The longer tail indicates the direction of the wind. The arrow (not used on actual weather maps) shows the direction in which the wind is moving. This is a westerly wind (blowing from the west).
SkillBuilder discussion Communicating 1. Study FIGURE10 . At what wind speed does a ‘strong breeze’ occur on the Beaufort scale? 2. What happens to trees and branches during a ‘gale’? 3. What wind speed is classified as a ‘hurricane/cyclone’ on the Beaufort scale?
FIGURE10 The Beaufort scale measures wind strength based on its visible effects.
0 Calm Less than 2 km/h Smoke rises vertically
1 Light air 2–5 km/h Smoke drift shows wind direction, wind vanes don’t move
2 Light breeze 6–12 km/h
Wind felt on face, wind vanes move
3 Gentle breeze 13–20 km/h Leaves and small twigs in motion, hair disturbed, clothing flaps
4 Moderate breeze 21–30 km/h Dust and loose paper move, small branches move
5 Fresh breeze 31–40 km/h Small trees with leaves begin to sway, wind force felt on body
6 Strong breeze 41–51 km/h Large branches move, umbrellas difficult to use, difficult to walk steadily
7 Moderate gale 52–63 km/h Whole trees in motion, inconvenience felt when walking
8 Gale 64–77 km/h Twigs broken off trees, difficult to walk
9 Strong gale 78–86 km/h People blown over, slight structural damage, including tiles blown off houses
10 Whole gale 88–101 km/h Trees uprooted, considerable structural damage
11 Storm 102–120 km/h Widespread damage
12 Hurricane/cyclone Greater than 120 km/h Widespread devastation
314 Jacaranda Humanities Alive 7 Victorian Curriculum Third Edition
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