How are wind gusts created?

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Why do some winds blow constantly, and some blow almost exclusively in gusts? What creates gusts? I know how wind is “made”, but how do gusts happen? If it’s the same thing, just on a smaller scale, wouldn’t it be like that all the time, and not depend on the direction of the wind?

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6 Answers

Anonymous 0 Comments

If you look at a wind map of the whole world, you’ll see it’s a mix of a bunch of different swirls of different wind speeds. That’s true on all scales. You’ll have the huge swirl of a large low pressure system, the medium-scale swirl of a thunderstorm in it, and small-scale eddies made by the wind as it moves past trees, buildings, etc. along with the flow.

A gust of wind is just your experience of one of those local regions of higher wind passing you by. In general, faster flows tend to be more turbulent (“swirly”), so they’re more common when it’s already windy.

Anonymous 0 Comments

Air is a fluid and so it helps to visualize it like water. Go down to a stream or pour water down a slope in your garden. The water will pile up behind objects then release in a gush, or a “gust” of water as it overwhelms that object. Now replace the rocks, shrubs, branches etc with buildings, trees etc. there’s also eddies, vortices and other types of air and water flow that cause gusts. These change shape as the landscape changes with wind because trees sway cars move etc. that big delivery truck moving slowly down the street sure changes how air flows between buildings, like dropping a rock in a stream.

Anonymous 0 Comments

What does hot air do? It rises.

So what about the air that moves in to take it’s place? That’s wind.

Anonymous 0 Comments

The easiest answer is that wind is like sound. Sound comes in waves due to the chaotic nature of the universe and so do winds.

Anonymous 0 Comments

Wind is caused when an area of high pressure balances with a nearby area of lower pressure. Think of blowing up a balloon, then letting the air out!

Anonymous 0 Comments

Air wants to move from areas of high pressure to areas of low pressure, caused by things like warm air rising up and colder air flowing in to occupy that space.

In a perfect, unchanging system this would happen at a constant speed. The thing is that we don’t live on a perfect, unchanging planet.

So the pressure differences and wind speed will vary depending on which areas are being heated or cooled and by how much – one day it may be really sunny and warm in one place and there will be a lot of air movement in that direction, the next it may be cloudy there but sunny elsewhere and the air patterns will change. Some days stronger, since weaker and so on. Because of this all the air is constantly moving direction and speed.

Alongside this the landscape also has a massive effect. Take a smooth flow of air and place a wall in the way. The air will start to build up behind the wall where it gets blocked and the pressure will rise until it is high enough to push the flow of air over the wall out of the way and release itself, at which point it will start to build up again. This means on the far side of the wall you will no longer get a smooth flow of air, but a flow that pulses along with the build-up and release of the air behind the way.
Repeat this with every mountain, valley and geological feature, not to mention any man made our natural objects like buildings and forests and add in the fact that the air is always changing as noted above too, and the nicer smooth airflow gets broken up into constantly changing and gusting winds.