Highest temperature in Paris on August 11?

Platform comparison

Market context

Polymarket is pricing this Paris temperature contract at **0% YES** in the early hours of settlement day, so the crowd is effectively assigning no chance to the listed outcome bands right now. On Polymarket, traders post and buy **USDC** positions on **Polygon**, with the eventual payout determined by the relevant **conditional tokens** resolving against Weather Underground’s daily observations for Paris-Le Bourget Airport Station, not the summary high/low figure.

That zero price sits against a weather backdrop that is far from benign. Polymarket’s own market page currently shows the leading outcome near **32°C**, while contemporary forecast services point to a hot day in Paris, with AccuWeather flagging a **yellow warning for extreme high temperature** and a high around the low 30s Celsius. Historical Paris August records show that mid-August can still produce extremes, with the 11 August record high on Météo-Paris listed at **39.5°C**, so the relevant question for traders is not whether August can run hot, but where today’s observed airport maximum lands within the contract’s bands.

For a Polymarket user, the practical catalysts are the live temperature updates and the timing of the final Weather Underground datapoint. The market description says revisions can be considered until the first datapoint for the following date is published, so late-day swings matter if Paris peaks after the morning. Traders will also watch whether the heat warning persists, whether cloud cover or rainfall suppresses the afternoon maximum, and whether the airport station reads differently from forecasts for central Paris; that basis risk is what can leave a seemingly obvious weather day resolving into a less obvious bucket.

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Methodology

This page reviews Highest temperature in Paris on August 11? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi UK, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

UK Frequently Asked Questions

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 Kalshi UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.