Weather Markets: a free weather prediction game where you beat the forecast

Weather is the one thing everyone has an opinion about and nobody keeps score on. So we built a place to keep score. Weather Markets is a free game where you predict tomorrow's weather in cities around the world and find out whether you can read the sky better than the official forecast. There's no money in it, there's nothing to sign up for, and there's no prize at the end. There are just points, a leaderboard, and the small satisfaction of being right about the rain when the app said sun.

It's the newest thing we've added to the site, and yes, it's a bit of a departure from our carbon calculators. Here's what it is and how it works.

What Weather Markets actually is

It's a play-money prediction game. The first time you make a pick you get 10,000 points, and you spend those points buying "yes" or "no" on simple weather questions. Will London top 24 degrees tomorrow? Will Tokyo get more than 1mm of rain? Will Sydney see a thunderstorm? If your pick turns out right, the shares you bought pay out. If it's wrong, they expire worthless. Your balance goes up or down depending on how well you called it.

The points are worth nothing in real terms. You can't deposit money, you can't cash out, and there's no jackpot waiting. That's on purpose. This is a game about forecasting, not a betting site, and we'd rather keep it fun than turn it into something you could lose your rent on.

How a single market works

Every question runs as its own small market with a live price. A price of 40 means the crowd currently puts the odds at about 40 percent. Price and probability are the same number here, which makes the whole thing easy to read. When you buy a side, the price drifts toward you, so being early and correct is worth more than piling in once everyone already agrees.

The flow goes like this:

• Pick a city, either by clicking it on the globe or choosing it from the list.
• Choose a question: temperature, rain, wind, or thunderstorm.
• Buy yes or no at the current price.
• The market closes at local midnight, before the weather day has even started.
• The next morning it settles, and the winning side gets paid 100 points per share.

We don't decide who won. Every market settles against the Open-Meteo historical archive, which is public, free, and the same record a meteorologist would check. If the archive says it rained, the rain markets pay out. Our job is to run the game and then stay out of the way.

The part that makes it interesting: beat the model

Here's the twist. The threshold for each question comes straight from the official forecast, so every market opens close to a coin flip. If the forecast says the high will land around 23.4 degrees, the temperature market asks whether it will clear 23.5. That means guessing the rough weather isn't enough. To win, you have to guess where the forecast is wrong.

Think the model is underrating a heatwave building over Madrid? Buy yes and see if you were right. Reckon that storm is going to fizzle before it reaches Miami? Take the other side. We started calling this "beating the model," and it turns out to be a lot more satisfying than refreshing a weather app.

A globe, not a spreadsheet

Most prediction markets look like a trading terminal. Rows of tickers, tight numbers, a wall of jargon. We went the other way. The main screen is a globe with every city on it, and the busiest cities glow brighter as people trade them. Click one and its markets slide open beside it.

The cities are spread on purpose, from Amsterdam and London across to Los Angeles, San Francisco and Seattle, then over to Tokyo, Seoul, Hong Kong, Singapore, Sydney and Auckland. Because they sit in so many time zones, there's almost always a market about to close somewhere, whatever hour you happen to open the page.

Free, and nothing to sign up for

You don't make an account. You don't hand over an email address. The first time you place a pick you claim a username, and that's the whole of it. Everyone starts on the same 10,000 points, and the leaderboard ranks people by how much they've grown their balance, not by who got there first. A brand new player and someone who has been at it for weeks are judged the same way, on return.

If you want to try it, you can play Weather Markets here. Pick a city, take a side on tomorrow, and find out whether you really do know better than the forecast.

Common questions

Is Weather Markets real-money gambling?

No. Every player uses points that have no cash value. There are no deposits, no withdrawals, and no prizes. It's a forecasting game, not a betting service, and it isn't regulated as one.

How do you decide who wins?

You don't take our word for it, and neither do we. Each market closes at local midnight and settles the next morning against the Open-Meteo historical archive. If the data hasn't been published yet, the market waits and tries again. No human picks the outcome.

Do I need an account?

No. You claim a username the first time you make a pick. There's no email, no password, and no signup form to fill in.

Is it really free?

Yes. It costs nothing, there's nothing to buy, and there's no real money anywhere in it.