Pronóstico: Highest temperature in London on July 4?

Platform comparison

Market context

On 4 July 2026, the London City Airport Station will record its peak temperature in degrees Celsius, a real-world metric that determines the resolution of this on-chain contract. Polymarket currently prices the “YES” outcome for a 28°C threshold at 0%, reflecting a market consensus that such warmth is virtually impossible under current conditions. Traders holding conditional tokens on the Polygon network, settled in USDC, are effectively betting against a heat spike that would require an extreme atmospheric anomaly.

Historical data frames this near-zero probability with stark clarity. July is London’s hottest month, with an average high of 21°C (72°F), yet even during the record-breaking July 2022 heatwave, the highest temperature observed in London was 40.2°C at Heathrow, not London City Airport [7]. London City Airport’s typical July highs range from 71°F to 87°F (22°C to 31°C), but the 28°C threshold remains a rare outlier for this specific station [6]. The 0% price aligns with the station’s modest thermal profile compared to western airports that captured the 2022 extremes.

Traders should monitor the Met Office’s daily highest gust and maximum temperature forecasts for London City Airport, as sudden shifts in southerly winds could alter thermal outcomes [4]. While no immediate announcements signal a heat event, the upcoming week’s forecast shows temperatures rising to 65°F (18°C) by Monday, suggesting a gradual warming trend rather than an abrupt spike [1]. The settlement window closes on 4 July 2026 at 12:00 UTC, leaving little time for late-stage volatility to impact the final resolution.

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 Polymarket Argentina, which mirrors the Polymarket order book directly.

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

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 Polymarket Argentina. 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Polymarket Argentina trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.