Highest temperature in London on August 18?

Platform comparison

Market context

The market seeks to identify the highest temperature recorded at London City Airport on 18 August 2026, measured in degrees Celsius via the Daily Observations table on Weather Underground. The settlement window closes at midday on that date, meaning the resolution source captures observations through the morning hours and any early afternoon readings before the cutoff.

August temperatures at London City Airport typically range between 19°C and 25°C, with historical highs occasionally reaching 28–30°C during warm spells. The 0% crowd probability suggests traders expect the market's upper threshold to fall below plausible August readings, or that the specific resolution methodology—prioritising the Daily Observations table over summary figures—creates ambiguity about which recorded value will be used. Weather Underground's granular hourly data sometimes differs from daily summaries, particularly when peak temperatures occur near midnight or in early morning hours before the settlement window closes.

The primary catalyst remains the actual weather pattern developing in mid-August 2026. Traders should monitor seasonal forecasts from the Met Office and European weather models as the date approaches, particularly whether high-pressure systems establish over the British Isles during that week. The precise timing of temperature peaks relative to the 12:00 UTC settlement deadline matters considerably; a hot day with its maximum at 14:00 would fall outside the resolution window, whilst a morning spike would be captured. Any discrepancies between Weather Underground's data sources should be flagged early, as the market explicitly designates the Daily Observations table as the binding resolution source.

Methodology

Sports-specific comparison page for Highest temperature in London on August 18?. Polymarket's live quote (Polygon order book) plus platform attributes for the three reference venues. Sports markets reward liquidity — Polymarket and Betfair are materially deeper than Kalshi or Manifold.

Resolution & payout

Sports markets typically settle on official final-whistle plus league confirmation. Polymarket uses UMA Optimistic Oracle with a source URL per contract — usually official league data feeds or ESPN/Soccerway. Two-hour dispute window, then smart-contract payout in USDC.

FAQ

When do sports markets resolve?

Typically within hours of the official final whistle. Polymarket uses UMA Optimistic Oracle with source URLs pointing at official league data feeds — e.g. the Premier League for EPL markets, UEFA for Champions League, FIFA for World Cup.

Can I bet on individual matches?

Yes, Polymarket lists every major Premier League / Champions League / World Cup match as its own market. Liquidity varies — top matches like El Clásico or a semi-final often have six-figure pools, lower-league games closer to three-figure.

Which sports markets are available?

Football (soccer) dominates — Champions League, World Cup, Premier League, La Liga, Bundesliga — followed by NFL, NBA, tennis Grand Slams, Formula 1, boxing/MMA. Resolution via official league source confirmation.

How fast do sports winnings settle?

Once the official league outcome is logged in the UMA Oracle (typically 1-2 hours after the final whistle), Polymarket's smart contract triggers USDC payout. To your wallet within minutes.

What's the difference between match odds and outright odds?

Match odds cover a single game ("Bayern beats BVB"). Outright odds are long-term aggregates ("Bayern wins the league"). Outright markets have deeper liquidity; match markets have faster resolution.