Highest temperature in Paris on July 13?

Platform comparison

Market context

Paris-Le Bourget is expected to face typical July heat on 13 July 2026, but the market prices a specific extreme outcome at just 1% YES, reflecting the rarity of record-breaking highs at this station. The contract resolves on-chain via USDC on Polygon, using conditional tokens to settle once Wunderground confirms the day’s peak Celsius reading for the airport.

Historically, Paris’s July highs average around 23°C, with the national record of 42.4°C set in 2019 at a different Paris site, not Le Bourget [2]. AccuWeather’s July 2026 forecast for Paris shows daily highs between 23°C and 36°C, suggesting the 1% probability aligns with the low likelihood of exceeding 36°C at this location [1]. No Le Bourget record approaches France’s 44.3°C southwest peak from 2022, reinforcing the market’s conservative stance [5].

Traders should monitor Météo-France’s daily heatwave bulletins and any red-alert announcements for Île-de-France, as these trigger immediate shifts in on-chain pricing. A recent NPR report on France’s June 2026 heatwave confirms that official alerts directly correlate with temperature spikes and market volatility [7]. Watch for updates on the 13 July forecast released by 6 AM UTC, which will determine whether the 1% YES price holds or adjusts before settlement.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is PolyGram. 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.