Highest temperature in London on July 12?

Platform comparison

Market context

London City Airport is currently experiencing sunny intervals with a high of 29°C today, 12 July 2026, while the prediction market for the day’s peak temperature shows a 0% crowd-implied probability for the YES outcome. On Polymarket, this contract trades on Polygon using USDC, where conditional tokens reflect the market’s near-zero confidence that the temperature will exceed the settlement threshold. The price action suggests traders believe the day’s heat will remain within standard summer bounds rather than triggering an extreme outlier.

Historically, London’s July highs at EGLC average around 22°C (72°F), with recent peaks in July 2022 reaching 40.2°C at Heathrow and St James’s Park, though EGLC itself has not recorded such extremes [2][6]. The current forecast for July 2026 shows daily highs between 21°C and 31°C, with today’s maximum at 29°C, well below the 40°C benchmark that would define a record-breaking event [1][5]. This historical context explains why the market assigns negligible probability to an extreme high, as typical mid-July conditions rarely breach 32°C at this specific station.

Traders should monitor the Met Office’s 7-day forecast updates and Wunderground’s real-time hourly logs, which serve as the official resolution source for this market [3]. Any sudden shift in southerly wind patterns or humidity spikes could alter the peak temperature, but current data shows moderate breezes and 88% humidity, limiting rapid heating [4]. With settlement closing at 12:00 UTC on 12 July, the final temperature reading will be locked in by 14:00 UTC local time, making the next two hours critical for final price adjustments before resolution.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in London on July 12? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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.

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.

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.