Highest temperature in London on June 25?

Platform comparison

Active sub-markets

Market context

The underlying event is the daily maximum temperature recorded at London City Airport on 25 June 2026, with current Met Office forecasts suggesting a daytime peak near 35°C amid an ongoing UK heatwave[1]. While the crowd-implied probability for a "YES" outcome sits at 0%, historical data frames this as a high-stakes weather anomaly rather than a certainty. Comparable cases include Kew Gardens recording 26.6°C as the hottest day of 2026 so far in May, yet recent local reports show maxima reaching 33.9°C on 23 June, indicating a rapid escalation in thermal intensity that challenges the current zero-probability stance[5][10]. The market’s 27% weighting for 30°C and 25% for 31°C suggests traders are hedging against the volatility of persistent high-pressure systems rather than dismissing the heat entirely[1].

Traders must monitor the Met Office’s hourly updates and the specific timing of the high-pressure ridge, as Wednesday’s forecast of 37°C could shift the settlement range if the heat persists into Thursday[6]. The primary catalyst is the Met Office’s ongoing heatwave declaration, which drives the persistent high temperatures expected across the capital[1]. Regarding accessibility, the German GlüStV and US CFTC frameworks create a complex regulatory backdrop for prediction markets, yet the "no-KYC up to $1,500" threshold allows retail participants to access this specific weather market without immediate identity verification, provided the trade value remains within that limit. This regulatory nuance means the market remains accessible to a broad audience despite the stringent oversight from German and American authorities, though participants should remain aware that larger positions may trigger compliance checks.

Sources: 1 · 2 · 3 · 4 · 5

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 Polymarket Legal UK, 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

Is this market available outside the US?

Polymarket Legal 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 Polymarket Legal UK?

Zero. Polymarket Legal 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, Polymarket Legal UK triggers a quick verification flow that finishes in minutes.