Two accounts on Polymarket made a combined $37,000 in profit by successfully betting on temperature anomalies. The outcome of the markets depended on the maximum temperature in Paris, based on data from the weather station at Charles de Gaulle Airport.
In both cases, the traders bet on a rare scenario and received payouts after the sensor briefly showed the required reading. The story now involves not only on-chain analysts and journalists, but also the police.
Temperature Anomalies
According to BFMTV, on April 6, the temperature at the station suddenly rose above 21°C and then almost immediately returned to its previous level. That spike allowed the market to resolve in favor of the winner, who received more than $16,000. Nine days later, nearly the same thing happened again: on April 15, the sensor showed 18°C for most of the day, then suddenly jumped to 22°C and immediately dropped back.
The second case was analyzed in detail by Bubblemaps. The analysts said the spike was not reflected at nearby stations. Just before the readings changed, one of the traders began buying NO positions on the 18°C outcome and, after the market resolved, exited with more than $21,000 in profit. In total, the two accounts made $37,000.
Who Manipulated the Thermometer?
Meteorologist Ruben Hallali said such short-term temperature changes looked extremely unlikely under natural conditions, especially on both dates.
“One can assume human interference by someone who understands how the sensors work and managed to raise the readings by exactly two degrees at the precise moment needed to settle the bet,” he said.
France’s national meteorological agency, Meteo France, has already filed an official complaint with the police. The agency accuses unknown individuals of deliberately interfering with the operation of automated data-processing systems.
Read also: