Highest temperature in Madrid on August 9?

Platform comparison

Market context

The underlying event is whether Madrid’s hottest reading on 9 August 2026 lands in a given Celsius band, with the market currently pricing **0% YES**. That makes the favourite effectively the *under* on an unusually hot outcome, while any value on the yes side would need a clear reason to expect a spike above the crowd’s assumed threshold.

On the historical frame, Madrid in August is hot, but the specific 9 August baseline is still usually well below extreme-heat levels. WMO’s climate page puts the mean maximum for 9 August at **36°C**, while Weather Journey shows an average high of **31.7°C** across the full record and a record high of **38.8°C** for 9 August, which was set in 2023.[6][1] That sits alongside recent history where 8 August reached **39°C** in 2023 and **37°C** in 2024 on World Weather Online, showing that high-30s are possible but not the median case.[7] In handicapper terms, the favourite is the broad heat band around the low-to-mid 30s, with the contrarian angle being a one-day overshoot into the upper 30s if the atmosphere turns exceptionally hot and dry.

For catalysts, the key dependency is the actual airport observation sequence on Weather Underground’s **Daily Observations** table, since that is the settlement source, not the summary high/low box. Madrid’s daily forecast products around this date have pointed to highs near the mid-to-upper 30s, with Weather Journey showing **36.1°C** for 2026-08-09 and AccuWeather’s August listing also clustering the day around the high 30s Fahrenheit-to-Celsius equivalent range.[1][8] Traders should watch whether any late-day heating, warm nocturnal start, or local wind shift allows the airport station to print above the consensus band; otherwise, the market’s 0% YES implies the crowd sees the settlement range as comfortably below the trigger.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Madrid on August 9? 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.

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