Highest temperature in Madrid on July 12?

Platform comparison

Market context

Madrid is currently experiencing the peak of its highest summer temperatures, with Barajas Airport serving as the official benchmark for the day’s maximum heat. The settlement hinges on a single Celsius reading from 12 July 2026, captured at the Adolfo Suárez Madrid-Barajas Airport Station via Wunderground.

Historical data from early July 2026 shows Madrid hitting 42°C on 5–6 July, marking a record-breaking spike well above the seasonal average of 35°C [2]. This recent extreme heatwave, which saw nine regions on alert and temperatures soaring to 42°C across Spain, suggests that a 0% probability for any meaningful high temperature is statistically anomalous given the current climatic trajectory [7]. Programmatic traders should note that previous July contracts resolved near the upper brackets when similar heat domes persisted, making the current zero-implied probability a potential mispricing relative to the 40–42°C range observed just days prior [2][5].

Traders monitoring this market must watch real-time Wunderground updates for the Barajas station, as the resolution source is strictly tied to that specific location’s daily maximum [market description]. The primary catalyst is the continuation of the intense heatwave dominating central Spain, which authorities expect to hold above 40°C until at least 7 July, with clear skies and dry conditions sustaining the thermal pressure [2]. Automated bots should query the Wunderground history API at 12:00 UTC to capture the official daily high, while conditional orders might be triggered if live feeds show temperatures breaching 38°C before the settlement window closes. The dependency on a single station means localized cloud cover or wind shifts at Barajas could disproportionately alter the outcome compared to broader metropolitan readings [market description].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Madrid on July 12? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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

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 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Polymarket Bot UK 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.