how to measure wind speed without an anemometer

How to measure wind speed without an anemometer? An anemometer is a commonly used instrument to measure wind pressure and speed.

But, what if you have to do it without this sophisticated tool? 

You may be amazed to discover that there exist effective techniques that can furnish you with a reasonably precise approximation of the speed of the wind.

Let’s find out how you can do that.

You can measure wind speed simply by looking at how the wind moves the trees, the flags, and the water and then estimate the speed using the Beaufort scale

Why Is It Hard to Measure Wind Speed Accurately?

challenges in accurate wind speed measurement

It is impossible to be 100% accurate when describing how fast the wind blows because the winds won’t cooperate by blowing at a constant speed.

We cannot see the wind, instead we feel it and can observe its effects. This makes measuring wind speed without an anemometer somewhat subjective.

The latest sensor technology takes measures in real-time and mathematically accounts for the gusting.

But day to day we rely on our previous experiences of the wind and our recall of how it impacts the world around us to help us determine when it is blowing a gale.

It helps us make informed decisions based on the most likely outcome. A survival skill enhanced by learning the basics of the Beaufort Wind Scale is worthwhile. 

Learn the Beaufort Wind Scale

learn the beaufort wind scale

The Beaufort Wind Scale uses observation and ranks winds according to the damage they cause.

Knowing classifications that match wind speeds with descriptions of damage provides a comparison that can help decide what is happening around you, at least weatherwise.

The Beaufort Scale is a standardized measure, just like inches, pounds or hours.

But, you do not need to remember details, such as the wind speed in knots and in miles per hour, you only need a general idea of the wind speed. Is it slow, fast, or extreme. 

More about the Scale

more about the scale

When we use the previous experience with the winds as a quick guide, the scale can be reduced down to just four broader categories,

0 – 2Calm gentle breezeWavelets, smoke rising vertically
3 – 6BreezyWaves, small leafy trees sway
7 – 9Big waves, sea foam,Whole branches or trees in motion
10 – 12  Storms and hurricanesViolent seas, structural damage, trees ripped up

We are so used to dealing with winds in our environment we barely register their impact when it’s calm.

However, when we judge the speed of the wind mentally, we use our own experience, first and second hand, as a personal Beaufort Scale. 

Fact: Observation is our greatest tool when it comes to determining the wind’s direction and speed and how it helps if we have a frame of reference.

How to Measure Wind Speed without an Anemometer?

measuring wind speed without an anemometer

Okay, so there is no anemometer. Not even a couple of cups and twigs but the circumstances are dictating that you need to find how fast the wind is blowing.

Perhaps you are on a balloon trip, surfing or kite flying, or you are trying to escape an island on a boat with a dodgy sail.

Whatever the case, you may or may not have concerns about accuracy but do not worry.

There are ways to achieve your goals:

Use a Pinwheel

When there is no anemometer, no worries. You can still make use of a pinwheel.

Structurally, pinwheels with their cupped blades, resemble the traditional anemometer and work the same way.

use a pinwheel

It is a simple method that consists of the following steps:

  • Hold the pinwheel into the wind.
  • Do the blades spin? There’s a wind.
  • Watch one blade. How fast is it spinning?
  • If you observe one single blade rotate three times, it is breezy.
  • If all the blades spin so quickly, they blend into one, it could be a strong wind or a gale, either way the winds are fast.

Flags, Airsocks and Ribbons on Sticks

Technically, these methods are used to judge wind direction but how they move provides an idea of the wind speed, especially how hard and how regularly the winds are gusting.

flags airsocks and ribbons on sticks

You do not need the real thing, just something light that can be lifted by the wind like a sheet of paper or a handkerchief fixed to a pole positioned higher up to catch the wind:

  • If there is no movement so that the sock, flag or ribbon lies still parallel to the pole, there is little or no wind.
  • If the flag, sock or ribbon is lifted so it flutters but doesn’t stay at an angle to the pole, it is a breeze.
  • If the material is stretched out at 90 degrees from the pole, it is a gale.
  • When the flag, airsock or ribbon is stretched out perpendicular to the pole and remains where you are in winds approaching a hurricane.

An Important Consideration

Watching the wind move a bit of something blowable on a stick to judge the wind speed is an age-old technique.

This stretches back to when civilizations discovered how to sail to navigate the oceans and later take advantage of trade winds.

Of course, they would not have judged the wind speed with a nylon windsock, instead, they used observations of the wind’s influence on the natural world

Listen to the Trees

listen to the trees

The movement of the windsock, flag and ribbon in windy conditions can be likened to the descriptions of the movements of trees as winds move up the rankings of the Beaufort Wind Scale.

The scale charts the development of winds into hurricanes as they progress in stages and thus what happens to trees:

  • Notice if trees begin throwing down debris quite early, losing leaves, twigs and dead branches in the gusts of breezes.
  • Check if they sway and bend, crack branches and fall and the developing wind whistles as it is compressed between them.

In strong winds, woods and forests are very noisy. But, in calm conditions the sound of the breeze in the trees is soothing. 

Fact: The sound of the breeze in calm conditions is described as so soothing it has been given a name, psithurism, which means whispering. 

Watch the Water and Waves

watch the water and waves

The surface of the water is very easily influenced by wind.

Ripples are recognizable effects and are characteristic of the winds in lower ranges of the Beaufort Wind Scale.

  • Stand still and observe the effect of an air current.
  • Notice how it pushes forward the surface of liquids by blowing on hot coffee or soup.
  • Use the same when checking how the ocean water behaves.
Fact: In storm surges, a sudden influx of ocean water that is abnormally high, it is the strong wind that pushes seawater over the topography of the shoreline. 

What Happens in High Winds?

what happens in high winds

In very high winds, ripples give way to mounting waves, some many feet high with considerable destructive power.

Like wind in the forest, in very fast winds you hear the thunder of the ocean before you see it.

Look for white water and foam created by the gale whipping up the top layers of the waves.

It has inspired many to stand in the wind to paint white horses galloping through the surf. 

Look at the Cloud Tops

Clouds are always a good indicator of the weather to come but they can be used to judge windspeed.

They form where air masses meet and fueled by evaporation they develop over warm equatorial waters, traveling towards land pushed in front of air currents attempting to equalize pressures.

In certain conditions, when air currents meet objects windshear forces air upwards and clouds develop vertically.

look at the cloud tops

Such clouds are indications of storms and reach up into the atmosphere for miles. They often lose their tops to the jet streams.

The fast-moving winds break clouds apart and line up the remnants in direction of the wind.

The jet streams not only shift north and south, also undulate, a motion that brings some of its currents in contact with the ground’s surface.

Fact: Observing a row of neatly pinched clouds in the sky is an indication the jet stream winds are nearby. 


How to measure wind speed without an anemometer?

While technology can give us the nitty-gritty details, having the ability to eyeball wind speed without a fancy anemometer is like having a secret superpower – practical and oh-so-enlightening.

By becoming a wind whisperer and carefully studying the way it tickles leaves, plays with flags, and creates water ripples, you will unlock the secrets of its strength.

Truly, it is a delightful dance of deciphering the secret language that Mother Earth whispers in our ears.