Highest temperature in London on July 9?

Platform comparison

Market context

London City Airport is currently experiencing an intense heatwave with daytime highs around 34°C, though thunderstorms are forecast to arrive late on 8 July and persist through 9 July, potentially disrupting the peak temperature reading [5][6]. The Met Office has issued amber heat alerts for London covering this period, confirming temperatures well above seasonal averages of 23–24°C [6][3].

Historical data from the 2026 UK heatwaves shows 35.1°C recorded in Wisley, Surrey on 9 July, marking the eighth consecutive day above 34°C nationally [7]. Despite this regional intensity, the current crowd-implied probability for the market sits at 0% YES, while the frontrunner outcome on Polymarket is 34°C at 50%, with 35°C at 37%, suggesting traders expect the airport station to record slightly lower peaks than the wider region [2].

Traders should monitor the timing of the incoming thunderstorms, as heavy rain and gusty winds forecast for late 8 July into 9 July could cap the maximum temperature before the settlement window closes [5]. The market resolves based on the highest temperature recorded at London City Airport Station via Wunderground, with USDC trades executing on Polygon using conditional tokens that update in real-time as new forecast data emerges [2]. Forecast models indicate the heatwave may persist until mid-July, but the immediate storm risk remains the primary catalyst for temperature deviation [6].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in London on July 9? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Polymarket Scam?, which mirrors the Polymarket order book at 0% fees.

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 Polymarket Scam?. 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.

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.