Highest temperature in Paris on August 19?

Platform comparison

Market context

On 19 August 2026, the highest temperature recorded at Paris-Le Bourget Airport will determine which range this contract settles into. The current Polymarket pricing reflects zero conviction behind any single temperature band, with conditional tokens trading at minimal USDC depth across the outcome buckets. This flat distribution suggests either genuine uncertainty about summer weather patterns two years forward, or insufficient liquidity to anchor trader positions on Polygon.

Historical August temperatures at Le Bourget show a median daily high around 25–26°C, though heat waves regularly push readings above 30°C. The summer of 2023 saw multiple days exceeding 32°C during the European heatwave; conversely, cooler Augusts have registered highs in the low 20s. The resolution mechanism's reliance on Weather Underground's Daily Observations table rather than the Day High & Low summary creates a technical distinction that occasionally matters when station equipment logs micro-fluctuations differently than headline figures. Traders should verify historical discrepancies between these two Wunderground data sources for Le Bourget specifically.

Catalysts shaping August 2026 conditions remain distant but traceable through seasonal climate patterns and Atlantic pressure systems. The North Atlantic Oscillation index, typically published by NOAA in real time, influences whether high-pressure systems stall over western Europe or allow Atlantic moisture to dominate. Any significant volcanic activity or solar forcing between now and summer 2026 could shift baseline temperatures, though such events remain unpredictable. Traders holding positions should monitor long-range ensemble forecasts released by Météo-France and ECMWF starting in July 2026, when 10–15 day outlooks become actionable.

Methodology

We track Highest temperature in Paris on August 19? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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

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 Polymarket Scam?. 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%.