The story of Windguru

February 10, 2020 | Surfing
Windguru: the popular online wind and wave forecasting website was founded in 2000 by Vaclav Hornik

Windguru is one of the world's first online weather forecasting websites for surfer, windsurfers, kitesurfers, and wave riders in general.

Today, it is one of the most popular wind and wave forecasting platforms in the world.

Windguru is used by water sports enthusiasts, world tour organizers, event promoters, fishermen, sailors, cruise and cargo ship captains.

There are even farmers visiting the website on a regular basis in search of detailed predictions for their crop fields.

The man behind Windguru.cz - the original and still the most popular URL - is Vaclav Hornik, a Czech windsurfer and kitesurfer.

It all started when his father shaped him a board when he was 13. Hornik also enjoyed listening to the weather forecasts on the radio, in the late 1980s, early 1990s.

When he got into the University of Economics, Prague, he had his first contact with a new reality called the internet.

That's when the young Vaclav starts searching for everything related to surf reports and weather forecasts.

Vaclav Hornik: the founder of Windguru | Photo: Hornik

"In the late 1990s, the internet was only beginning, it was pretty expensive, and not really widely available yet," Hornik tells SurferToday.

"Maybe you remember the connections with modems, connection speeds of 33.6 kbps, and download speeds of 4.2-KB/sec."

Suddenly, he found out that there was something called prediction models, so he started studying the topic compulsively.

The first step was to develop his own personal website with several links to weather forecast services.

And because he was already an accomplished programmer, Vaclav Hornik created a page that extracted data from reliable sources and reformatted it into a spreadsheet table.

"I was a keen windsurfer, always looking for forecasts, and I was also pretty much interested in computers and programming."

"So, I thought of processing the available public data and created a colorful forecast table for several local spots where I usually went windsurfing," explains Vaclav.

But the entrepreneur wanted a more detailed forecast for a particular place.

Vaclav Hornik: the Czech entrepreneur is a passionate windsurfer and kiteboarder | Photo: Hornik

So, he customized and adjusted variables for four Czech Republic spots located in popular windsurfing lakes and dams.

But how difficult was it to get the information he needed back in the late 1990s?

"The only source I remember were forecasts broadcast via radio and TV. Obviously, wind forecasts are not really interesting to normal people."

"If they actually said something about the wind, it was something like: 'there will be 3-to-7 meters per second, southwest wind.'"

"So, you really only got a very basic idea, and the decision to go or not was usually to look at the trees around - if they were moving enough, then you should go," recalls the founder of Winduru.

While in college, Hornik realized his future was not going to be spent around accounting - what he really liked was computers.

So, after getting his degree, Vaclav joined Czech Republic's web hosting provider, Globe Internet, where he developed his programming skills.

When Windguru started growing strong, he left and made his project a full-time job.

Let us not forget that, back in the day, there were no smartphones or surf cams, so it was hard to figure out the current wave and wind conditions at a given beach.

To check if it was worth it or not, surfers had to get to the spot to read the ocean conditions.

Vaclav Hornik: the man behind Windguru studied Economics, but programming and computers have always been his passion | Photo: Hornik

The Global Expansion of Windguru

By the late 1990s, Vaclav had already his country fully covered. So, he started replicating his model for new foreign locations.

The first non-European spot analyzed by Windguru was Maui, Hawaii's windsurfing Mecca.

The experience was a huge success, and soon after, there were more online users coming from outside of his country.

Hornik kept his original spreadsheet table formula forever. Why? Because it was working, and the feedback was that it was accurate and precise.

The founder of Windguru uses the model adopted by the National Oceanic and Atmospheric Administration (NOAA) in the United States.

NOAA's formula is a global model that is freely available to anyone.

At the time, it had a resolution of about a hundred kilometers, but today it is definitely more precise and detailed.

What Vaclav Hornik did was to tweak NOAA's model and adapt it to the uniqueness of each spot, including geomorphologic modeling.

In 2004, Windguru launched a pro subscription version with more detailed, accurate, reliable, and up-to-date data predictions. And the website's legendary blue server looked like this:

Windguru's 2004 server: one of Vaclav Hornik's first weather forecast computing machine | Photo: Hornik

Hornik teamed up with the Institute of Computer Science of the Czech Academy of Science to buy servers that currently work for the online wind-and-wave forecast website.

Windguru's pro version was a success and was a turning point in Hornik's life, as it became not just a hobby but also a full-time job.

But delivering a weather forecast is a complex technological challenge.

Windguru is powered by several servers and computing clusters that process the website itself, the database, and the forecast model runs.

And then, Hornik started expanding Windguru's area of analysis to the Canary Islands, South Africa, South America, etc.

Windguru is not perfect, and never will be because - like any other forecasting tool, it will always be a prediction.

Hornik lives well with that.

On an April Fool's Day, he even shared a forecast of 10-meter waves, sunny and clear skies for on an awful day at the Nechranice Reservoir.

And what was the most unusual request he had from users?

"There's always one question that comes to my mind. Someone once asked me: 'We will have a wedding in two months. Will it be raining?"

Windguru: a screenshot taken in 2004

The Present and Future of Windguru

Today, the Czech entrepreneur is an all-round waterman. Or at least, he tries to.

"I was a windsurfer for many, many years, but later - maybe in 2008 - I became a kitesurfer, too. I think it happened to many people," reveals Vaclav Hornik.

"Wave riding is something that is not really easy for someone who lives in Central Europe. But when I'm on holiday, somewhere in a place with wind and waves, I try to ride them on a kite. It's the best thing, and I love it!"

Today, Vaclav Hornik is a family man with children. But he still plans his holidays based on the wind conditions for a given region.

On January 2020, Windguru celebrated its 20th anniversary.

In the future, Windguru plans to expand the network of local weather stations that share real-time data with world users.

These portable gadgets can be installed at surf schools, apartments with a balcony facing the beach, or even near inland water bodies.

Vaclav Hornik tells SurferToday that "the most popular spots checked at Windguru depend on the time of the year, but Tarifa is one of the most visited, alongside several spots on the Portuguese coast, in western France, and Cape Town."

Windguru's 2019 server: modern surf forecasting requires powerful computers | Photo: Hornik

The mastermind behind Windguru.cz believes that there are several challenges ahead for surf and weather forecasting.

"To make them more reliable is always a challenge. We will also need more computing power [see Windguru's 2019 server below], better models, but it will always be difficult and unreliable to predict to forecast for more than several days in advance. The atmosphere and the weather are too much chaotic."

But, as of today, Hornik says Windguru delivers fairly accurate surf reports and "usable" forecasting tools.

"It's only a prediction, and will never be 100 percent perfect. If you accept that sometimes the forecasts fail, I think it still helps to find great wind and waves quite well," adds Vaclav.

The man behind Windguru has ideas that he hopes to implement in the surf forecasting website.

But, does he plan to manage Windguru until he retires, or would he be interested in trying other things in life?

"That is a good question. I was always thought about it, especially when I was sometimes asked if I had plans to sell Windguru, or if I was looking for an investor," reveals Vaclav Hornik.

Vaclav Hornik: Windguru is his passion and is not for sale | Photo: Hornik

"I understand that the common dream road map for startup companies is to have an idea, find investors, make it a big company, sell it and get rich - that's the short, classic description of success."

"But I realized that this is not for me. I don't think I would be able to create something else that would satisfy me more than what I have."

"I really value the freedom that I have to do what I like, the way I like. It's a great feeling when I see that people like the service, and that pushes me to carry on."

"I can't really imagine what would happen if I would exchange Windguru for money or something else. I am scared just to think of it."

Windguru is a steady, consistent, and extremely useful and helpful business platform supported by ads and pro subscriptions.

And may it continue to help wind and wave riders enjoy the time of their lives in the water.