Highest temperature in Hong Kong on August 8?

Platform comparison

Market context

Hong Kong’s highest temperature on 8 August is the figure the Hong Kong Observatory will publish as the day’s **Absolute Daily Max** once the daily extract is finalised, and that is what will settle the market. The current crowd-implied probability of **0% YES** sits well below the kind of outcome suggested by Hong Kong’s August climatology, where the 1991–2020 normal for 8 August includes a daily maximum around **31.7°C** and a mean temperature in the high 20s, with one recent August record day reaching **36.3°C** at the Observatory on 8 August 2015.[5][1]

Read across comparable cases, this contract has historically been the kind of weather market that can move sharply on a single hot afternoon rather than on the morning forecast. Hong Kong’s own recent August summaries show that the city can still produce exceptionally warm days late in the month, including an Observatory maximum of **34.4°C** on 8 August 2020, while 2024 was described by the Observatory as an “exceptionally hot August” with a mean daily maximum of **32.3°C**.[10][18] That leaves a clear gap between a zero-priced market and the practical risk that one strong heating day, if it develops, can easily push the final reading into the upper bands.

For traders, the key catalysts are the Observatory’s short-range forecast updates, hourly readings, and any thunderstorm or typhoon signal changes, because cloud, rain and onshore flow can cap the peak much more quickly than broad seasonal averages suggest.[3][6] At 3 a.m. local time the Observatory already reported **29°C** at its headquarters, which points to a warm start and leaves room for further upside if sunshine holds through late morning and early afternoon.[6] The main cross-platform comparison here is that sportsbook-style pricing, if available, would normally track the weather forecast more tightly than prediction-market sentiment, but the visible crowd price is currently far more bearish than the recent temperature pattern would justify.[6][18]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on August 8? 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.

UK Frequently Asked Questions

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

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.

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.

What are the best prediction markets for UK traders in 2026?

For UKGC-regulated markets: Betfair Exchange (sports, politics) and Smarkets (sports, politics, lower commission than Betfair). For broader global event prediction: Polymarket (deepest liquidity, 0% fee, USDC settlement). For US-regulated option: Kalshi (USD, limited UK payment options). Most serious UK traders use a combination of Betfair for regulated sports and Polymarket for broader markets.