Polymarket users win big off Paris weather data glitch

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French police are investigating whether someone tampered with a weather sensor at Charles de Gaulle airport to make money on prediction market bets. Temperatures rose by several degrees on the evenings of 6 April and 15 April, increases that coincided with a flurry of well-timed bets on Polymarket. The site, which is used to bet on everything from war to football, runs markets on the peak daily temperatures of several cities. Over $500,000 was wagered on how hot Paris would get on 6 April, compared to $176,000 the day before. It is not known what caused the temperature spikes. One theory posits a well-placed hairdryer.