Pronóstico: Highest temperature in London on August 5?

Platform comparison

Market context

Polymarket is pricing this London City Airport temperature contract at **0% YES**, which means the market is currently treating a hit to the relevant Celsius range as essentially unpriced. The underlying event is the day’s *highest* recorded temperature at London City Airport, so the practical question for a user holding USDC on Polygon is whether the noon UTC settlement cut-off can still be reached by the day’s warmest part of the forecast profile, with the final outcome determined by the Wunderground daily history page rather than by headline city forecasts.

That zero implied probability sits against a fairly ordinary August London backdrop rather than an extreme one. Current forecast data cluster around the low-to-mid 20s Celsius, with one source showing a 25°C high and another set of models ranging roughly from 24.3°C to 25.7°C, while long-run August averages for London are closer to the low 20s and daily highs often sit around 21–22°C.[1][3][7][11] For a range market, that matters because the contract is about the *single highest* reading, not the average; a brief warmer spike at the airport can matter more than the day’s general feel. Comparable August-day patterns in London history also tend to be modest rather than exceptional, with recent sample ranges around the low 20s and only occasional pushes into the mid-20s Celsius.[5][9]

The main catalysts for traders are the morning forecast updates, any late shift in cloud cover or wind, and whether the warmest window lands before the 12:00 UTC settlement cut-off. Forecast feeds published overnight and early this morning point to sunny intervals or partly cloudy conditions, with low rain risk but enough model spread to leave room for a small upward surprise in the airport reading.[1][3][4][13] Because the market resolves from Wunderground’s station history at London City Airport, not from city-wide averages, the relevant dependency is the station-level maximum temperature print rather than broader London weather commentary.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Pronóstico: Highest temperature in London on August 5? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Polymarket Qué Es, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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 Polymarket Qué Es. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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 Polymarket Qué Es 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.