Windspeed
in MPH |
Description
- Visible Condition |
| 0 |
Calm smoke
rises vertically |
| 1
- 4 |
Light air
direction of wind shown by smoke but not by wind vanes |
| 4 - 7 |
Light
breeze wind felt on face; leaves rustle; ordinary wind
vane moved by wind |
| 8 - 12 |
Gentle
breeze leaves and small twigs in constant motion; wind
extends light flag |
| 13 - 18 |
Moderate
breeze raises dust and loose paper; small branches are
moved |
| 19 - 24 |
Fresh
breeze small trees in leaf begin to sway; crested
wavelets form on inland water |
| 25 - 31 |
Strong
breeze large branches in motion; telephone wires
whistle; umbrellas used with difficulty |
| 32 - 38 |
Moderate
gale whole trees in motion; inconvenience in walking
against wind |
| 39 - 46 |
Fresh gale
breaks twigs off trees; generally impedes progress |
| 47 - 54 |
Strong
gale slight structural damage occurs; chimney pots and
slates removed |
| 55 - 63 |
Whole gale
trees uprooted; considerable structural damage occurs |
| 64 - 72 |
Storm very
rarely experienced; accompanied by widespread damage |
| 73+ |
Hurricane
devastation occurs |
