Highest temperature in Madrid on July 21?

Platform comparison

Market context

Madrid's maximum temperature on 21 July 2026 will be measured at Adolfo Suárez Madrid-Barajas Airport, the city's principal weather station, with settlement determined by Wunderground historical data. The 0% crowd-implied probability across prediction markets suggests traders are pricing in either extreme confidence in a specific temperature band or minimal liquidity in this particular contract.

July temperatures in Madrid typically peak between 35–40°C, with historical records showing 21 July has recorded highs ranging from 32°C to 38°C over the past two decades. The city experiences consistent summer heat patterns driven by Iberian thermal dynamics, making extreme outliers (above 42°C or below 30°C) statistically unlikely for this date. Comparable European weather markets on fixed dates show that when crowd probability collapses to zero, it often reflects either a dominant consensus on a single temperature band or sparse trading activity rather than genuine certainty about the outcome.

Traders monitoring this contract should track European weather forecasting updates from AEMET (Spain's national meteorological agency) as July 2026 approaches, particularly any anomalous pressure systems or heat waves affecting the Iberian Peninsula. The settlement window closes at midday on 21 July, meaning real-time temperature readings from the airport station become the definitive measure. Cross-platform comparison reveals whether sportsbooks or other prediction venues have priced temperature ranges differently, though traditional weather betting remains concentrated on seasonal aggregates rather than single-day maxima at specific locations.

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

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 PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.