The Hair Dryer Heist: How Two Traders Allegedly Beat the Weather Market

On a chilly April morning in Paris, Meteo-France meteorologists noticed something strange: a weather sensor at Charles de Gaulle Airport had spiked by several degrees in a matter of seconds - an anomaly that no nearby station could explain, and that no forecast had predicted.

A $34 Tool Against a Billion-Dollar Platform

The prediction market Polymarket allows users to bet on real-world outcomes, including whether daily temperatures in Paris will exceed set thresholds. On April 6 and April 15, 2026, the sensor readings crossed those thresholds in moments. Two traders - using the usernames "Hoaqin" and "xX25Xx" - had placed bets on exactly those outcomes at long odds. Hoaqin netted roughly $14,000 from the April 6 spike. xX25Xx walked away with $21,398 from a $119 stake on April 15 - a return of around 180 times the original bet.

The Allegation

Reports alleged someone walked up to the unguarded sensor near the airport perimeter and pointed a battery-powered hair dryer at it. The claim has not been authenticated by authorities, and no suspects have been named. What is confirmed: Meteo-France found physical signs of tampering at the sensor and filed a criminal complaint with the Roissy Air Transport Gendarmerie Brigade for alteration of an automated data processing system.

Polymarket Paid Out Anyway

Despite the investigation, Polymarket chose not to cancel or reverse the bets. The contracts were settled as valid, and the traders kept their winnings. The platform quietly switched its Paris temperature data source to a sensor at the nearby Paris-Le Bourget Airport, citing concerns about the Charles de Gaulle station.

Where Things Stand

As of late April 2026, French authorities have not identified or charged anyone in connection with the sensor readings. The alleged method - if confirmed - would represent one of the most low-tech exploits in prediction market history: approximately $35,000 extracted with a tool that retails for around $34.