Highest temperature in London on June 8?

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Active sub-markets

Market context

On 8 June 2026, the highest temperature recorded at London City Airport will determine which range this market resolves to. The Polymarket contract currently prices all temperature bands at 0% YES, reflecting the standard state of unresolved future weather contracts weeks in advance. Settlement depends on Wunderground's historical data feed for that specific station, with the resolution window closing at midday UTC on the day itself.

London's June temperatures historically cluster between 18°C and 24°C, though extremes have reached 28°C in recent decades during early summer heatwaves. The Met Office records show June 2022 saw temperatures peak at 24°C in central London, whilst June 2019 recorded 26°C during an anomalous warm spell. These precedents matter for calibrating expectations: a reading above 25°C would represent notably warm conditions, whilst anything exceeding 27°C would signal exceptional heat requiring sustained high-pressure systems over the British Isles.

Traders monitoring this contract should track the European weather pattern forecasts from mid-May onwards, particularly the position of the jet stream and any developing Atlantic blocking patterns that could drive continental air masses northward into the UK. The Met Office's monthly outlook, typically released around 16 May, will provide early signals about June's expected temperature regime. Additionally, any significant volcanic activity or solar variability affecting atmospheric circulation in the preceding weeks could shift baseline conditions, though such events remain inherently unpredictable at this distance.

Methodology

This page is a comparison snapshot: one live quote (Polymarket), four reference venues with their key attributes, and a single execution path — every trade button routes to Kalshi UK, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

FAQ

Is this market available outside the US?

Kalshi 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.

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.

What does it cost to trade on Kalshi UK?

Zero. Kalshi UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

Do I need to KYC for this market?

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