Traders on Polymarket are generating outsized returns by betting on daily temperature outcomes in cities worldwide, making weather prediction markets one of the platform’s fastest-growing segments.
Notably, the opportunity has attracted both human traders and automated strategies, which capitalize on gaps between forecast models and market pricing.
In one instance, on-chain data indicates that one trader on April 26 converted $505 into $10,100 on a Karachi high-temperature bucket priced at $0.5, then repeated similar 1,900% gains on Paris and Ankara bets within the same week.
A day earlier, a second trader scaled $186 into $6,630 on a Wellington reading bought at $1.4, part of a pattern that has produced returns as high as 49,000% on buckets priced as low as $0.1 in cities such as Lucknow and Atlanta.
Controversy on weather predictions
However, the trades have also faced controversy. On April 15, a trader turned $119 into more than $21,000 after a Paris temperature market briefly spiked to 23 degrees Celsius at the Charles de Gaulle Airport station, while the rest of the day remained below 18 degrees, and nearby stations showed no change.
A similar irregularity affected the same sensor on April 6, resulting in additional payouts estimated at $14,000 and pushing total profits from the two events to roughly $35,000.
To this end, French authorities opened an investigation after Météo-France filed a criminal complaint alleging tampering with the unsecured airport sensor.
Online speculation centered on a portable hairdryer or lighter briefly heating the probe to cross key thresholds. Polymarket responded on April 19 by switching Paris resolutions to a more secure station at Le Bourget Airport.
Meanwhile, one active account has now placed more than 4,800 predictions, routinely turning $60 stakes into thousands or $7 into nearly $700.
Notably, the profits from this weather-betting approach rely on monitoring ensemble weather forecasts and entering positions where models rate the outcome as far more likely than the current share price implies.
With hundreds of fresh temperature contracts launching daily across major cities, participants can compound small edges at high frequency, with resolutions often arriving within hours based on official station data.
