Highest temperature in London on July 26?

Platform comparison

Market context

On 26 July 2026, London City Airport's weather station will record a daily high temperature in Celsius. The market currently prices all outcome ranges at 0% probability on Polygon, suggesting either incomplete liquidity or a technical settlement issue rather than genuine uncertainty about whether the airport will register any temperature reading at all. Resolution depends on Wunderground's historical data feed for EGLC station, which captures hourly observations throughout the day.

London's July temperatures have ranged considerably across recent decades. The 2022 heatwave saw London exceed 40°C for the first time on record, whilst typical July highs cluster around 23–25°C. City Airport, situated on the Thames estuary, often records slightly cooler readings than central London due to water proximity and maritime influence. Historical July extremes at or near the airport span from lows of 18°C in cooler years to peaks approaching 35°C during sustained heat events. The settlement window closes at midday UTC on 26 July, meaning traders must account for potential afternoon temperature rises after the cutoff.

Climate forecasting for summer 2026 remains subject to seasonal uncertainty, though the UK Met Office publishes monthly outlooks approximately two weeks before each period. Traders should monitor late-June forecasts for anomalies in Atlantic pressure patterns and jet stream positioning, both of which drive whether continental heat penetrates northwestward into the British Isles. Any official heat-health alerts issued by the UK Health Security Agency in the days preceding 26 July would signal elevated temperatures, though such alerts typically accompany readings above 30°C rather than extreme heat.

Methodology

We track Highest temperature in London on July 26? 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

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

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.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.