How to calculate wind speed
You can determine how fast the wind is blowing using the chart below. It provides useful information when you are on the road or when you observe the impact of the wind from the inside.
The table is an easy reference, but when you are outdoors remember that the wind can present many hazards. Be aware that the wind dehydrates you, regardless of the air temperature; Wind chill lowers your body temperature and can damage your skin or even blind you in a snowstorm. Wind power increases exponentially compared to wind speed.
When hiking in windy conditions, always bring extra water and extra clothing, hat, and gloves. Plan your route so that it is protected from the prevailing winds and be sure to arrive or build a shelter before dark.
To supplement your knowledge, build an anemometer to obtain accurate measurements and compare your observations with the table below.
Speed of air in motion Name What we can see
0 mph (0 km / h) Calm Smoke rises
1-3 mph (1-5 km / h) Light air Smoke drift
4-7 mph (6-11 km / h) Light breeze Leaf rustle
8-12 mph (12-19 km / h) Gentle breeze Leaves and twigs
13-18 mph (20-29 km / h) Moderate breeze Branches are moving
19-24 mph (30-39 km / h) Cool breeze Young trees sway / white caps in water
40-50 km / h (25-31 mph) Strong breeze Large branches move
32-38 mph (51-61 km / h) Moderate gale Whole tree sway
39-46 mph (62-74 km / h) Fresh wind Twigs break / walking is challenging
47-54 mph (75-87 km / h) Strong gale Branches, street signs knocked down
55-63 mph (88-102 km / h) Uprooted trees
103-121 km / h (64-72 mph) Storm force Damaged structures
73+ mph (122+ km / h) Hurricane force Widespread devastation