Story perspectives

Meteo France Accuses CDG Sensor Tampering, $37K Payouts, Switches Data.

4/24/2026

Summary

Meteo France Complains

Meteo France filed a complaint with the Roissy Gendarmerie Brigade alleging manipulation of Charles de Gaulle Airport temperature sensors.
Two Polymarket contracts using the highest temperature on April 6 and April 15 paid out $37,000 as sensors spiked 4 °C and 5 °C, yielding payouts of $16,000 and $21,000 respectively.
After the controversy Polymarket shifted future Paris temperature contracts to Paris-Le Bourget data on April 19.

Summary

Hallali Claims Manipulation

Meteorologist Ruben Hallali said the Paris temperature jumps could not be explained by normal conditions and suggested manipulation.
A trader earned over $21,000 from NO shares on the April 15 jump, while a French-media-cited account made $14,000 on April 6 and $20,000 on April 15.
Nearby stations recorded no matching temperature spikes at the times of the Paris readings.
Polymarket users posted real-time comments calling the events manipulation and insider trading.

Summary

Paul Marquis Blames

Paul Marquis, founder of E-Meteo Service, said a heating device near the probe most plausibly caused the spikes.
He added the station sits near the runway perimeter and is reachable from a public roadside area, allowing unauthorized access.
After the controversy, Polymarket, despite being banned in France, moved its Paris weather contracts to Paris-Le Bourget Airport on April 19.

Summary

Kalshi Fines Candidates

Kalshi suspended and fined three congressional candidates for betting on their own elections.
Polymarket, Kalshi let users wager on temperature, rain and snowfall in cities.
Météo France spokesperson Elenie Alfera said it filed a police complaint over suspected tampering of automated data system.
French authorities opened an inquiry into manipulation of the Charles de Gaulle temperature sensor after the April 15 spike, prompting calls for oversight of data feeds used by prediction markets.

History

Historical Context

Following the 2008 financial crisis, the French government enacted stricter data integrity regulations in 2013 to enhance market transparency. This move was prompted by past issues of misinformation in financial markets. Concurrently, Météo France's discovery of temperature sensor manipulation at Charles de Gaulle Airport led to a police inquiry, highlighting ongoing concerns about data reliability in various sectors.

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Meteo France Complains

Meteo France filed a complaint with the Roissy Gendarmerie Brigade alleging manipulation of Charles de Gaulle Airport temperature sensors.
Two Polymarket contracts using the highest temperature on April 6 and April 15 paid out $37,000 as sensors spiked 4 °C and 5 °C, yielding payouts of $16,000 and $21,000 respectively.
After the controversy Polymarket shifted future Paris temperature contracts to Paris-Le Bourget data on April 19.

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