Highest temperature in Madrid on August 16?

Platform comparison

Market context

The market seeks the highest temperature recorded at Madrid-Barajas Airport on 16 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 range or insufficient liquidity to establish meaningful odds. Madrid's August temperatures typically peak between 32–38°C, with historical data from the airport station showing that days exceeding 40°C remain rare but not unprecedented during heat waves.

August 2026 falls within the typical summer peak for the Iberian Peninsula, when Atlantic high-pressure systems dominate and afternoon temperatures at the airport frequently reach the mid-to-upper 30s. Historical precedent matters here: Madrid recorded 40.3°C on 16 August 1990, and more recently experienced several days above 38°C during the 2022 European heat wave. The zero probability assignment likely reflects traders clustering around a narrow band rather than genuine uncertainty about whether a reading will occur. Any outcome between 30–40°C would represent the consensus sweet spot, with extreme readings (below 25°C or above 42°C) carrying genuine contrarian value if atmospheric patterns shift unexpectedly.

Traders should monitor European weather forecasting updates from mid-August 2026, particularly whether Atlantic systems push northward or if continental heat dominates. The specific resolution mechanism—using Daily Observations rather than Day High & Low summaries—creates a technical dependency on Weather Underground's data quality and methodology. Any discrepancies between weather services could matter at range boundaries, particularly around 35°C and 40°C thresholds where temperature ranges typically cluster.

Methodology

We track Highest temperature in Madrid on August 16? 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

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 Who Will Win. 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%.