Highest temperature in Madrid on July 3?

Platform comparison

Market context

The underlying event is the highest temperature recorded at Madrid-Barajas Airport on 3 July 2026, measured in degrees Celsius and sourced from Wunderground. Today, Polymarket prices the "YES" outcome for this contract at 0%, implying the crowd believes the temperature will fall outside the specified range. This on-chain market, settled in USDC on the Polygon network using conditional tokens, reflects a consensus that extreme heat is unlikely for this specific date, despite the broader seasonal context.

Historical data frames this probability sharply: Madrid’s July highs typically range from 32°C to 39°C, with 2026 already proving Spain’s hottest year since records began, with temperatures 1.6°C above normal[4]. In June 2026, Madrid hit 40°C during the first official heatwave, and July 2025 saw peaks exceeding 42°C under Saharan air masses[2][3]. Yet, the 0% price suggests traders expect a break from these extremes on 3 July, perhaps due to a lack of sustained Saharan inflow or a shift in Atlantic patterns.

Traders should monitor the European Centre for Medium-Range Weather Forecasts for Saharan air mass announcements and the timing of Atlantic low-pressure systems, which could cool the region. Recent Reuters reporting confirms Spain’s sweltering June heatwave, but no official forecast yet predicts a repeat for early July 3[2]. The settlement window ends 2026-07-03T12:00:00Z, so real-time Wunderground updates will be the final catalyst. With 2026’s heat already causing hundreds of excess deaths, any deviation from the norm carries significant on-chain weight[5].

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 PolyGram, 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 PolyGram. 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.

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.