Highest temperature in London on August 2?

Platform comparison

Market context

London’s hottest reading on 2 August will be set by the peak at London City Airport Station, and the current crowd price puts **0%** on a winning outcome at settlement, which is far below the live market’s view on the temperature band itself. Polymarket’s order book is centred on **27°C at 52%**, with **26°C at 26%** and **28°C at 18%**, so the contract is being priced as a fairly tight spread around the mid-to-high 20s rather than a real outlier event.[1]

That is broadly consistent with comparable weather signals, which point to a warm but not extreme London day. Forecasts in the market description cite Met Office expectations of a **27°C** daytime maximum under strengthening high pressure, light winds and southerly flow, while other sources cluster in the **26–28°C** range, including 27.1°C from Metaweather and 28.0°C from WeatherAPI.[1][7] Recent UK coverage also notes that southern England has been running above seasonal norms, but the last major heat spikes have still been modest by long-run standards compared with the 30°C-plus episodes seen earlier in the 2026 summer.[14][16]

For traders, the key catalysts are the afternoon warmth, cloud cover and any timing mismatch between the day’s peak and the settlement window, because this market resolves off the highest recorded temperature rather than a daily average.[1] The market also specifies that revisions to readings within the timeframe count only until the first datapoint for the following date is published, so late adjustments can matter if the station posts an update after the peak.[1] On a cross-platform basis, prediction-market pricing is clearly more specific than sportsbook-style weather lines, but the consensus from forecast services still favours a mid-to-upper 20s outcome rather than an unusually cool or hot reading.[1][7]

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 Best Prediction Markets, 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

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.

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.

Do I need to KYC for this market?

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

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.