Wind Force Number |
Description of Wind |
Wind effect locally |
Speed MPH |
0 |
Calm |
Calm, smoke rises vertically |
1 |
1 |
Light air |
Direction of wind shown by smoke drift, but not by wind or weather vanes |
1-3 |
2 |
Light Breeze |
Wind felt on face, leaves rustle, wind or weather vanes move |
4-7 |
3 |
Gentle Breeze |
Leaves & small twigs in constant motion, wind extends light flags |
8-12 |
4 |
Moderate Breeze |
Wind raises dust and loose paper, small branches move |
13-18 |
5 |
Fresh Breeze |
Small trees in leaf begin to sway. Little crested wavelets form on inland waters |
19-24 |
6 |
Strong Breeze |
Large branches in motion, umbrellas used with some difficulty |
25-31 |
7 |
Near Gale |
Whole trees in motion, becoming difficult to walk against wind |
32-38 |
8 |
Gale |
Twigs break off trees, progress is generally impeded |
39-46 |
9 |
Strong Gale |
Chimney pots, slates & tiles may be blown off, other slight structural damage |
47-54 |
