Highest temperature in Madrid on July 21?

Platform comparison

Market context

Madrid's weather on 21 July 2026 will be determined by atmospheric conditions across the Iberian Peninsula during the peak of summer. The settlement hinges on the highest temperature recorded at Adolfo Suárez Madrid-Barajas Airport, the official meteorological station for the city, measured in Celsius and resolved through historical weather data on Wunderground.

July temperatures in Madrid typically range between 28°C and 36°C, with extremes occasionally exceeding 40°C during heat waves. Historical records show that mid-to-late July represents the warmest period of the year, though the specific daily maximum varies considerably year to year depending on Atlantic pressure systems and Saharan air intrusions. The 0% crowd probability suggests traders are either uncertain about the temperature ranges offered or expect conditions substantially below typical July norms—an outcome that would require unusual atmospheric blocking patterns or persistent cloud cover during the settlement window.

Traders should monitor European weather forecasts from mid-July 2026, particularly tracking high-pressure systems over the Mediterranean and any Saharan dust events that typically amplify heating. The Spanish meteorological agency (AEMET) publishes extended forecasts roughly ten days in advance; these updates will clarify whether anticyclonic conditions dominate or whether Atlantic systems bring cooler, cloudier weather. Airport station readings can differ slightly from city centre measurements due to local surface characteristics, so the specific location matters for precise temperature outcomes.

Methodology

This page reviews Highest temperature in Madrid on July 21? 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 Prediction Today, which mirrors the Polymarket order book at 0% fees.

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.

FAQ

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.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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 Prediction Today trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.