Gusty kitesurfing and turbulence: when to stay ashore

You feel gusty wind the moment you're out. The kite pulls evenly for a while, then a gust yanks you off the water, and a few seconds later the kite drops. With gusty kitesurfing, I'd stay ashore if I couldn't control the kite in the gusts, the launch was in turbulent wind behind trees, buildings or a hill, the wind was offshore without active rescue cover arranged in advance, or a storm was coming.

If you've only had a handful of independent sessions, start in mild conditions at a spot you know. Being nervous about gusts is normal, and it's a healthy instinct. Even experienced riders need to handle the full wind range on their chosen kite, with room between them, the beach and obstacles. A smaller kite alone won't fix conditions where you lose control or the wind could change sharply.

What the gust number in a forecast means

A forecast gives you 2 numbers: wind and gusts. Wind is the average, usually over 10 minutes in Windy. Gusts are the highest speed the wind briefly jumps to, and you don't add them to the average. If Windy shows 15 knots gusting 25, the gust hits at 25 knots.

Look at the full range: how strong the gusts are and how far the wind drops between them. The average isn't the minimum, and the gap between average and gusts alone won't tell you whether to ride. 15-20 knots with the odd gust to 25 is a very different session from 15-20 knots gusting 30. If your forecast is in metres per second, 10 knots is roughly 5 m/s.

A gust usually lasts less than 20 seconds. There's no time to work out a plan while it's happening, so the reaction has to be one you've already practised. When reading a wind forecast, check the direction and changes through the day, then compare it with what's happening at the spot.

Where turbulence comes from

The most common cause of choppy, gusty wind is an obstacle the air has to cross before it reaches you. Behind trees, houses or a hill the airflow breaks up, and instead of a steady pull you get lulls and gusts taking turns. Trees and buildings create rougher turbulence than sand dunes.

I know this from snowkiting at Moldava in the Czech Ore Mountains. Up on the plateau, when the wind blows from the forest and I'm close to the trees, the kite behaves turbulently and it's unpleasant. The fix is to ride a bit further away.

Don't choose your launch just by its distance from the trees. A rough estimate for turbulence downwind is 7 times the obstacle's height: 140 m for a 20 m obstacle. Gusts can still be felt further away. Behind windbreaks, reduced wind speeds can be measured up to 30 times their height, or 600 m in this example. These figures illustrate how far an obstacle can affect the wind; they aren't safe kiting boundaries. Wind speed and direction, obstacle shape and density all matter. Assess the launch with someone who knows the spot, and don't launch there if it's turbulent. Right in front of a building or fence the airflow is disturbed too, deflecting and compressing against it.

There's a broader rule as well: the more land, fields, villages and forest the wind has crossed, the more gusts it picks up. Inland lakes and fields almost always get wind that has travelled over land, so expect gusts more often there than on a coast where the wind comes off the sea.

Offshore wind

Wind blowing from the beach out to the water (offshore) is a trap. It comes over land, so it tends to be unstable, and if something goes wrong it carries you away from the shore into open water. Avoid it for your first independent sessions. Even an experienced rider needs active rescue cover arranged in advance: a boat already on the water, a pilot trained for deep-water rescue and someone ashore who knows you're riding and watches you.

When assessing wind direction, distinguish side-onshore, blowing diagonally towards the beach, from direct onshore. For your first independent sessions, I'd look for a suitable side-onshore spot with clear space and help arranged for launching and landing. Direct onshore requires you to ride upwind away from the beach immediately; a mistake can send you back onto the shore. Direction alone isn't enough: assess local currents, obstacles and space with someone who knows the spot.

Storms and fronts: the gusts you can't forecast

Gusts caused by obstacles are fairly predictable. You know the spot and which directions blow clean and which blow messy. Gusts from a front or a rain shower are very hard to predict in advance.

A thunderstorm pushes strong wind out ahead of itself. Forecasters name the leading edge a gust front, and it sometimes comes with a low shelf cloud. When you see a dark wall of cloud approaching, land and pack up straight away. Waiting until it arrives is too late. If you're still on the water, don't park the kite overhead: a strong gust can loft you from 12 o'clock.

For the worst case, your quick release, the handle that releases the bar from your harness, has to be second nature, so your hand finds it without looking. Using it is a basic kitesurfing safety skill to master before riding independently.

When to go and when to stay on the beach

When a gust catches you on the water

Ride slower through a gust. Push the bar out, shift your weight onto your heels, edge harder and point further upwind. The board digs in and acts as a brake. If you let the gust speed you up, the board rises, there's less drag, you speed up more, and it ends in a crash.

In strong gusty wind, don't leave the kite at 12. Keep it lower, around 10 or 2 o'clock. If your edging and speed control aren't solid yet, you'll need the kite a little higher, because a low kite pulls you sideways too hard. That's also why a beginner needs a smaller kite in gusty wind than an experienced rider.

If the wind drops slightly and you're still riding, try to keep your speed. You can sheet in and turn the board's nose more towards the kite. In a deeper lull, work the kite, but don't choke it by holding the bar in. If it starts flying backwards and dropping trailing edge first (backstall), ease the bar out. When there isn't enough wind to ride but you can still keep the kite flying, focus on it and weave it slowly back and forth.

In light, gusty wind the kite drops most often when you stop: while putting the board on, while body dragging, during a transition. Don't wait with the kite at 12. Put the board on with the kite lower and start riding straight away. Once you're moving, the kite sees steadier wind and drops far less often.

Kite size for gusty days

On a gusty day, size for the stronger end of the range, closer to the gusts. With a smaller kite you'll sit through a lull for a moment, keep the kite flying and wait. With a big kite, a gust near the beach can drag you up onto the sand.

For working out size from your weight and the wind, see what size kite do I need. On a gusty day, enter a wind speed closer to the gusts in the kite size calculator.

Where to learn riding in gusts

You can get used to gusts gradually. Start on a mildly gusty day when you can handle the full wind range with your gear, and leave plenty of space around you. Set up further from hazards and closer to the water, so you've got room for a mistake.

On the kite safari in Egypt I rode around islands where there's nothing, just sand, and the wind blows all the time. The organiser lists a steady 15-25 knots at Tawila. The main kite days have morning and afternoon riding, with evening video coaching scheduled on days 3-6 so you can see your own riding. The crew helps with launching and landing and provides boat rescue. They choose spots for the wind, and riding follows the conditions.

The crew also organises downwinders, longer rides with the wind between islands.