Highest temperature in London on May 30?

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Active sub-markets

Market context

On 30 May 2026, the highest temperature recorded at London City Airport will fall into one of several defined ranges. The settlement uses Wunderground's historical weather data for that specific station, which sits in East London and typically records slightly warmer conditions than central London due to its location near the Thames estuary. The 0% crowd probability suggests traders currently expect no consensus on which temperature band will occur, reflecting genuine uncertainty about late May weather patterns rather than a settled forecast.

Late May in London historically produces highly variable conditions. Over the past decade, maximum temperatures on 30 May have ranged from 16°C to 24°C, with an average around 19–20°C. The 2020 heatwave pushed May temperatures considerably higher across southern England, though London City Airport's readings remained more moderate than inland sites. This variability explains why prediction markets on specific daily temperatures attract limited initial liquidity—the outcome depends on transient weather systems rather than structural trends, making early positioning difficult without meteorological conviction.

The key catalyst is the 10–14 day forecast window closing in on late May 2026. Traders monitoring the Met Office and European Centre for Medium-Range Weather Forecasts (ECMWF) models from mid-May will gain material signal about whether Atlantic low-pressure systems or continental high-pressure ridges will dominate. Deposit flows via Klarna and SEPA transfers typically accelerate as settlement approaches and confidence in forecasts hardens, driving book depth and tightening spreads across temperature bands.

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 Klarna UK, which mirrors the Polymarket order book directly.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket Klarna 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?

Polymarket Klarna 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.

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