Highest temperature in London on July 6?

Platform comparison

Market context

The underlying event is the peak temperature recorded at London City Airport on 6 July 2026, a date currently forecast to reach 65°F (14°C) with high humidity and falling pressure, suggesting a cool start rather than a heat spike. Historical data frames this probability starkly: July is London’s hottest month, with an average high of 72°F, yet recent records show variability, including a UK July maximum of 36.9°C at Heathrow just days prior, while London’s own top ten hottest days recently peaked at 32°C. The crowd-implied probability of 0% YES reflects a consensus that the temperature will fall below the market’s threshold, likely under 30°C, given the current southerly wind, 88% humidity, and 1012mb pressure, which typically suppress extreme heat.

Traders should watch the Met Office’s hourly updates for any sudden shifts in wind direction or cloud cover, as a change to easterly winds could bring warmer air from continental Europe, a catalyst that recently drove temperatures to 32°C during a summer heatwave. The settlement window ends 2026-07-06T12:00:00Z, meaning the final resolution depends on the Wunderground record for the entire day, not just the morning forecast. Contrarian value might sit in the underdog if a late afternoon heat spike occurs, but the current 0% probability suggests the market is pricing in a cool, damp day with no significant heatwave, making the favourite the safe bet unless a rapid weather change is announced. The value spot lies in the contrarian angle only if a sudden pressure drop or wind shift is confirmed, as the consensus remains firmly on the cool side.

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

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'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.

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 Who Will Win trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.