Highest temperature in London on June 11?

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Active sub-markets

Market context

The highest temperature recorded at London City Airport on 11 June 2026 will determine the settlement range for this market. The resolution mechanism draws directly from Weather Underground's historical data archive for that specific station, with the settlement window closing at noon UTC on the day itself.

London's June temperatures typically range between 18–24°C, though heat waves can push readings into the high 20s or low 30s. The 0% crowd-implied probability across prediction markets suggests traders are pricing in either extreme confidence in a specific temperature band or genuine uncertainty about which range will ultimately contain the day's high. Historical June records at London City Airport show variability: whilst the station rarely records temperatures below 15°C or above 28°C in early-to-mid June, the 2022 heatwave demonstrated how rapidly conditions can shift. Comparable markets on UK summer temperatures have typically seen probability mass cluster around the 20–25°C range during this period.

Traders should monitor the Met Office's medium-range forecasts from early June, which typically gain accuracy within seven to ten days of the target date. Seasonal patterns—including the North Atlantic Oscillation and any developing high-pressure systems over continental Europe—will shape the atmospheric setup. The specific timing of any frontal systems crossing the British Isles in the days preceding 11 June will be critical, as will any anomalous warmth or coolness established in the preceding week. Current divergence between prediction-market odds and historical June climatology warrants close attention as the settlement window approaches.

Methodology

We track Highest temperature in London on June 11? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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?

On Best Prediction Markets UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Best Prediction Markets UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Best Prediction Markets UK triggers a quick verification flow that finishes in minutes.