You’ve finally found the ultimate co-founder. They’re smart, they deliver, and they have impressive experience. What can go wrong?

Well, it seems A LOT can go DREADFULLY WRONG.

Your friends probably have horrific co-founding stories. Your lawyer has more. And the Internet can inspire infinite nightmares.

– Ok, let’s review Catastrophic Scenario #27
– The kraken attack?

So before starting our first company together, we (Julien and Bastien) tried to identify what we were up against.

We wanted to find the situations that could cause tension between us, and discuss them way before they could divide us and compromise the company.

Here are the 7 toxic scenarios we currently want to…

ClimateList now displays flights prices, allowing travelers to visualize the cheapest flights for each month just bellow the weather calendar:

Try the app at

This feature is powered by Skyscanner. Prices are available for 195 of the world’s busiest cities and refreshed approximately twice a day.


The “From” city is set by default to the city having the airport with the highest passenger traffic in your country. You can change it and choose your favorite currency:

ClimateList was inspired by my own struggle with making travel plans optimized for the best seasons. It’s a visual alternative to my hours of Googling and reading precipitations charts.

The app is a map with a large slider for selecting the month:

Try the app at

The story

In 2015 I left my job at a french tech startup to travel and start working on my own projects. Over the next 1.5 years I saw Nepal, Slovenia, Austria, Japan, South Korea, Vietnam, Cambodia, Thailand, New Zealand, Hong Kong, Portugal, Spain and more.

Some countries have a very complex configuration of many diverse climates and trying to simplify them for ClimateList is a nightmare. That’s not the case with Portugal, where things are relatively simple:

Try the app at

Climate calendar

Portugal is divided in 2 climate zones:

1- North

A Temperate Mediterranean climate:

Russia has just been updated on ClimateList with 10 new zones fitting the country’s multiple climates more accurately. Here is how it looks:

Try the app at

Climate calendar

The 10 zones compared over time:

On ClimateList, Mali is now divided in 2 climate zones, respectively having a Warm Desert and a Warm Semi-Arid / Tropical Savanna climate.

Mali climate map, try it on ClimateList

Climate calendar


A Warm Desert climate with 6 months of extreme heat:

On ClimateList, Canada was until now divided using the country’s administrative provinces. It was a terrible idea as these provinces are very large and encompass different climates. The result was quite misleading.

Here are the new 7 climate zones:

Try the app at

Climate calendar

The 7 zones compared over time:

I’m on a mission of building the ultimate app for deciding when to travel. It’s called ClimateList and its main component is a map showing the location of the best weather for each month of the year.

The ClimateList app

How it works

I compute a “Best weather” indicator based on the average temperatures and precipitations in each country. The green color indicates a country where the weather is not too cold, not too hot, and not too rainy for a particular month:

From Tropical to Oceanic, Australia is home to a surprising range of climates, with their own ideal seasons for travelers.

On ClimateList, the country is divided in 7 climate zones. As for the rest of the map, green indicates the months with the best weather.

Australia climate map, view interactive version on ClimateList

Climate calendar

Here is the weather in the 7 climate zones of Australia compared over time:

You should pick the dates of your trip to India carefully, or you could experience extreme rainfalls, dangerous heat, or both.

On ClimateList, India is divided in 6 zones where travel is recommended at a different time of the year. As for the rest of the map, green indicates the months with the best weather.

India climate map, view interactive version on ClimateList

Climate calendar

Here is the weather in the 6 climate zones of India compared over time:

Bastien Petit

Maker of CashNotify —

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