Highest temperature in London on June 2?

Market context

On 2 June 2026, the highest temperature recorded at London City Airport will fall into one of several defined ranges in Celsius. The market currently prices all temperature outcomes at 0% probability across the board on Polymarket, suggesting either a technical issue with the conditional token pricing or extreme uncertainty that hasn't yet resolved into meaningful odds. Traders are staking USDC on Polygon to claim positions on which range will contain that day's peak temperature, with settlement determined by historical data from Wunderground's London City Airport Station records.

London's June temperatures typically range between 15–22°C, with historical highs occasionally reaching 25–28°C on warmer days. The 30-year average high for early June sits around 20°C. Exceptionally hot June days—those exceeding 28°C—occur roughly once per decade in London, making extreme heat outcomes statistically unlikely but not impossible. The 2022 heatwave saw June temperatures reach 32°C in parts of southern England, though London City Airport's readings tend to run slightly cooler than central London figures.

Traders monitoring this contract should track the UK Met Office's extended forecast as June approaches, particularly any warnings for high-pressure systems or continental air masses that could drive temperatures upward. The settlement window closes at 12:00 UTC on 2 June, meaning the market resolves based on the full calendar day's peak temperature. Any significant weather pattern shifts in May 2026—such as early blocking highs or unusual warmth—would shift the probability distribution, though current pricing suggests the market has not yet priced in meaningful conviction around any specific range.

Methodology

We track Highest temperature in London on June 2? 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

Resolution source: This market settles from the official publication at https://www.wunderground.com/history/daily/gb/london/EGLC. A proposer submits the result to the UMA Optimistic Oracle on Polygon, the two-hour challenge window opens, and the smart contract pays out in USDC.

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?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 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 reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.