Highest temperature in London on July 12?

Platform comparison

Market context

London City Airport is currently experiencing a warm, sunny Sunday with temperatures reaching 29°C, yet the market for the highest temperature on this specific date in July 2026 remains priced at 0% YES. This implies the crowd believes the day will fail to breach the settlement threshold, despite live conditions already sitting near the upper end of the typical July range. The 0% probability suggests a consensus that the day will remain moderate, ignoring the immediate heatwave signals visible at the station.

Historically, July is London’s hottest month, with average highs at this airport sitting around 22°C (72°F), though extreme spikes are well-documented. The city recorded a record 40.2°C in July 2022, and recent daily reports show maximums of 31.2°C on 10 July 2026, indicating a persistent warm spell [7][8]. The current pricing appears to undervalue this historical volatility and the recent trend of above-average temperatures, creating a potential contrarian angle where the “underdog” outcome of a high temperature holds significant value against the favourite of a cool day.

Traders should monitor the Met Office’s seven-day forecast updates and real-time Wunderground data for any sudden shifts in cloud cover or wind direction that could suppress the peak temperature [3]. With southerly winds currently at 8 mph and humidity at 88%, the atmosphere is primed for heat retention, but a change in pressure could alter the outcome [5]. The settlement relies strictly on the daily maximum recorded at EGLC, making the timing of the afternoon peak critical; if the 29°C reading holds or rises through 3 PM, the 0% price becomes a clear mispricing of the actual weather risk.

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 Who Will Win, 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?

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

Is this market available outside the US?

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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 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.

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.