Highest temperature in London on July 12?

Platform comparison

Market context

London City Airport faces its peak summer heat on 12 July 2026, with the market betting on which Celsius bracket will capture the day’s highest reading. Historical data shows July is London’s hottest month, averaging a high of 72°F (22°C), though recent years have seen spikes well above this baseline [4]. An intense heatwave gripping southern England earlier in July 2026 pushed daytime highs to around 34°C before thunderstorms arrived, suggesting the atmosphere remains primed for extreme temperatures [6]. Given this context, the current 0% crowd-implied probability for a “YES” outcome appears misaligned with the market’s own frontrunner of 28°C at 49–56% probability, indicating a notable divergence between the binary sentiment and the range-based consensus [2].

Traders should monitor real-time updates from Wunderground, the official resolution source, alongside live forecasts from the Met Office and BBC Weather for London City Airport [3][7]. The key catalyst is whether the heatwave’s residual warmth persists through the weekend, as forecasts for 11–12 July indicate sunny intervals with highs near 84°F (29°C) [7]. Recent daily reports show maximum temperatures reaching 31.2°C on 10 July, reinforcing the likelihood of a 28°C or 29°C peak [8]. With settlement ending at 12:00 UTC on 12 July, any sudden shift toward thunderstorm activity could cap the temperature, but the prevailing trend points to sustained warmth above seasonal averages [6].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, 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

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.

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?

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.