Highest temperature in London on July 5?

Platform comparison

Market context

The real-world event centres on the peak heat recorded at London City Airport on 5 July 2026, a date historically prone to summer highs. July is the hottest month for this station, with average highs reaching 22°C (72°F), while recent forecasts suggest daily peaks between 28°C and 30°C under clear skies and light winds[2][5]. Current crowd-implied probability sits at 0% YES, indicating the consensus believes the temperature will not breach the specific range in question. This contrarian stance ignores the seasonal tendency for London to experience heatwaves in early July, where temperatures frequently exceed 30°C, creating a potential value spot for those betting on the upper end of the range[2][6].

Traders should monitor the Met Office maximum temperature announcements and any developing weather patterns linked to southerly airflow, which can drive heat into the city. Recent data shows a maximum temperature of 29°C recorded nearby, with falling pressure and breezy coastal winds that may either amplify or dampen the heat depending on cloud cover evolution[3]. While no specific heatwave announcement has been made yet, the forecast for 5 July indicates mostly clear skies, a key catalyst for high temperatures that could push readings toward the 30°C threshold[5]. The absence of severe thunderstorm clusters in the immediate forecast further supports the likelihood of sustained heat, contrasting with the 0% probability that currently undervalues this seasonal reality[4].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in London on July 5? 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

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

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.

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.

Do I need to KYC for this market?

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