Highest temperature in Guangzhou on August 10?

Platform comparison

Market context

The event here is the **highest temperature recorded at Guangzhou Baiyun International Airport on 10 August 2026**, measured from Weather Underground’s **Daily Observations** table rather than the summary high/low box. In prediction markets, a **YES** share pays out if the market’s stated condition is met; a **NO** share pays if it is not, so the price is the crowd’s implied probability of that exact outcome. With the market currently at **0% YES**, traders are effectively saying the listed temperature band is not expected to be hit under the resolution rules.

Guangzhou’s August climate is typically very hot and humid, with historical summaries putting average daytime highs around the low 30s Celsius and many late-summer days reaching the mid-30s. Recent market commentary and forecast guidance have pointed to peak temperatures in the **36–38°C** range, which helps explain why this contract is trading around the upper end of the outcome grid rather than near cooler bands. For a new reader, the key point is that the contract is not about what feels hottest or what a forecast app shows at midday; it resolves only to the single highest value logged in the observation table before the first datapoint for the next day is published.[8][10][13][16]

The main catalysts to watch are the **intraday observation updates** on Weather Underground, because the official peak can be revised upward or downward until the next day’s first reading appears. Cloud cover, afternoon thunderstorms, wind shifts and the timing of peak sunshine can all move the maximum by a degree or two, which matters when the market is split across narrow Celsius bands. AccuWeather’s current forecast for Guangzhou shows a very hot day with highs around **100°F/38°C**, reinforcing the risk that the final observation lands in one of the upper brackets rather than the median outcome.[12]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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.

UK Frequently Asked Questions

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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.