Highest temperature in Paris on May 31?

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Active sub-markets

Market context

On 31 May 2026, the highest temperature recorded at Paris-Le Bourget Airport will fall into one of several defined ranges. Polymarket currently prices all temperature brackets at 0% probability, reflecting either thin liquidity or a technical settlement issue rather than genuine forecasting consensus. The market resolves using Wunderground's historical weather data for that specific station, with settlement occurring at 12:00 UTC on the day itself. Traders accessing this contract on Polygon will need USDC to purchase conditional tokens representing their chosen temperature band.

Paris in late May typically experiences highs between 20–24°C, with occasional warm spells pushing toward 28–30°C. Historical records from Le Bourget show that temperatures exceeding 30°C on 31 May are rare but not unprecedented; the station recorded 29.8°C on 31 May 2020 and 28.1°C in 2019. May heatwaves do occur in northern France, though they remain statistical outliers. The current 0% pricing across all brackets suggests either insufficient market depth or a display glitch rather than genuine forecasting data.

Traders should monitor European weather forecasts from mid-May onwards, particularly outputs from Météo-France and ECMWF models. High-pressure systems tracking northward from the Mediterranean or Atlantic blocking patterns could drive anomalous warmth into the Paris region by late May. The settlement window closes at noon UTC, meaning morning temperatures recorded before that cutoff determine the outcome. Any significant heatwave warnings issued by French authorities in the weeks preceding 31 May would likely shift market pricing substantially.

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). The odds column is filled only where we have clean data — that avoids the made-up numbers that get a network demoted when search engines cross-check against the source venue.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does it cost to trade on Polymarket UK?

Zero. Polymarket UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.