Highest temperature in Madrid on July 22?

Platform comparison

Market context

Madrid’s airport is being priced as a **39°C** day, with the market implying **77%** on that outcome and **21%** on **40°C**. That makes 39°C the clear favourite, while 40°C is the main underdog with genuine upside if the city sees a late-day spike or the airport runs a touch hotter than the city forecast. The crowd is effectively anchored to a high-but-not-extreme heat outcome, which leaves limited room for lower bands unless the forecast softens materially before the settlement cut-off.[1][2]

The historical frame for a market like this is straightforward: when Madrid is in a heatwave regime, the distribution often clusters tightly around the upper 30s, so the key question is usually whether the maximum stays just below a round-number threshold or tips over it. Today’s weather coverage points to a dry setup with **0% rain chance** and a forecast maximum of **39°C**, which supports the favourite and explains why the consensus sits there rather than on 38°C or lower.[2] The contrarian angle is 40°C, because once inland heat builds under clear skies, airport readings can overshoot headline city forecasts by a degree or so.[2]

For traders, the main catalysts are the latest local forecast updates, any shift in cloud cover or winds, and whether official guidance keeps Madrid pinned at 39°C into the afternoon. The market resolves on the highest reading at Adolfo Suárez Madrid-Barajas Airport Station from Wunderground, so the exact airport observation matters more than the citywide forecast, and even a small change in conditions can move the settlement band.[1][2]

Sources: 1 · 2 · 3

Methodology

This page reviews Highest temperature in Madrid on July 22? 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.

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

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.

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.

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.

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.