Highest temperature in Madrid on July 12?

Platform comparison

Market context

Madrid is currently baking under an intense summer heatwave that has pushed temperatures well above seasonal averages across central Spain, with the city recording highs of 42°C earlier this month during the July 4–7 event[2]. Despite this recent extreme activity, the Polymarket contract for the highest temperature on 12 July 2026 shows a crowd-implied probability of 0% for the YES outcome, suggesting traders believe the specific temperature bracket in question is unlikely to be hit despite the prevailing heat[1]. Historical data for July in Madrid typically sees average highs around 35°C (95°F), though the 2026 forecast indicates a range of 32°C to 39°C, meaning the market is pricing in a significant deviation from the norm if the YES condition were to materialise[1].

Traders monitoring this on-chain USDC market on Polygon should watch for any official meteorological announcements from AEMET regarding the duration of the current heatwave, which authorities expect to persist above 40°C until at least 7 July[2]. The settlement relies exclusively on Wunderground data from the Adolfo Suárez Madrid-Barajas Airport Station, making the precise timing of the daily peak critical for conditional token resolution[1]. With the first half of 2026 already confirmed as Spain’s hottest ever recorded, the dependency on whether this extreme trend continues through mid-July remains the primary catalyst for price movement[10]. Recent reports indicate nine regions are on alert for extreme heat, with temperatures hitting 42°C in some areas, reinforcing the volatility traders face as the settlement window approaches[7].

Sources: 1 · 2 · 3 · 4 · 5

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 Kalshi UK, which mirrors the Polymarket order book directly.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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

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.