Highest temperature in Paris on August 18?

Platform comparison

Market context

The market seeks the highest temperature recorded at Paris-Le Bourget Airport on 18 August 2026, with settlement based on Weather Underground's Daily Observations table rather than summary figures. The crowd currently assigns zero probability to any outcome, suggesting either extreme confidence in a particular temperature band or insufficient liquidity to establish pricing. August temperatures at Le Bourget typically range between 18°C and 28°C, with historical August averages around 24–25°C, though extremes have occasionally exceeded 30°C during heatwaves.

Paris experienced notably elevated temperatures during summer 2022 and 2023, with August peaks reaching 32–34°C during European heatwave conditions. The 0% probability reading appears disconnected from realistic meteorological variability; even in cooler-than-average Augusts, daily highs rarely fall below 16–17°C at the airport station. This suggests the market may be mispriced if traders are anchoring to a single temperature band rather than acknowledging the natural spread of outcomes across multiple ranges.

Traders monitoring this market should track European summer weather patterns as August 2026 approaches, particularly Atlantic pressure systems and any developing heat domes over continental Europe. The Copernicus Climate Change Service and Météo-France seasonal outlooks, typically released monthly, will provide directional signals on whether 2026's August is tracking toward above-normal or below-normal temperatures. Le Bourget's coastal-influenced microclimate can differ from central Paris readings, making the specific station data critical for accurate settlement.

Methodology

This page reviews Highest temperature in Paris on August 18? 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 Who Will Win, which mirrors the Polymarket order book at 0% fees.

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.

UK Frequently Asked Questions

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.

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.

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%.