Highest temperature in Madrid on August 17?

Platform comparison

Market context

On 17 August 2026, the highest temperature recorded at Madrid-Barajas Airport will fall into one of several defined ranges. The market resolves using the Daily Observations table from Weather Underground rather than summary figures, a distinction that matters when intraday peaks diverge from published highs. Madrid's August climate typically produces readings between 28 and 38 degrees Celsius, though extremes outside this band occur irregularly.

Historical August data from Madrid-Barajas shows that temperatures exceeding 40°C occur roughly once per decade, whilst readings below 25°C are exceptionally rare in mid-August. The 0% crowd probability suggests traders are pricing in either an unusually cool spell or treating the market as illiquid relative to the underlying volatility. August 2023 saw Madrid peak at 36.5°C; August 2022 reached 39.4°C. These recent precedents anchor expectations around the 35–39°C band, though climate patterns and specific atmospheric conditions in 2026 remain unknowable at present.

Traders should monitor European weather forecasting updates from late July and early August 2026, particularly from ECMWF and Météo-France, which typically issue reliable 10–14 day outlooks. Heatwave alerts from Spain's meteorological agency (AEMET) would signal elevated tail-risk probabilities toward higher ranges. Settlement occurs at 12:00 UTC on the resolution date, meaning the final intraday peak matters; afternoon convection and urban heat island effects around the airport can produce sharp spikes. USDC settlement mechanics mean traders should account for gas costs and exchange liquidity when sizing positions in lower-probability ranges.

Methodology

This page reads Highest temperature in Madrid on August 17? on-chain. Polymarket's quote comes directly from the Polygon order book — the only comparable venue with on-chain settlement. Kalshi (USD, off-chain), Betfair (GBP/EUR, off-chain) and Manifold (play-money) are listed alongside for venue context. Every CTA routes to BTC Prediction, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

UK Frequently Asked Questions

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