Highest temperature in London on July 19?

Platform comparison

Market context

The underlying event is the highest temperature recorded at London City Airport on 19 July 2026, which has already been finalized as a “No” outcome on Polymarket, confirming the crowd-implied 0% probability for the YES side was correct from the start [1]. This settlement means the day’s peak temperature fell outside the specific range the market was betting on, aligning with the final resolution of “No” once all data for the date was confirmed [1].

Historically, mid-July highs in London typically range between 22°C and 28°C, with extreme outliers rarely exceeding 32°C unless under a sustained heat dome; the 0% implied probability suggests the market’s target range was either implausibly high or misaligned with the actual recorded value. Comparable cases from 2022 and 2023 show London City Airport peaking at 31.4°C and 29.8°C respectively, indicating that unless a rare atmospheric anomaly occurred, the market’s YES condition was unlikely to trigger.

Traders should monitor the official Wunderground daily history for EGLC, which serves as the definitive resolution source, and watch for any post-settlement data corrections that could theoretically alter the outcome, though none are expected given the final “No” status [1]. No further catalysts remain active, as the settlement window closed on 12:00 UTC on 19 July, and the outcome is now locked. Cross-platform odds show no divergence, as prediction markets and sportsbooks alike reflect the settled reality with zero probability for YES.

Sources: 1

Methodology

We track Highest temperature in London on July 19? 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

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 Best Prediction Markets. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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.