Highest temperature in Hong Kong on August 10?

Platform comparison

Market context

Hong Kong’s **10 August maximum temperature** is the event that will settle this contract, using the Hong Kong Observatory’s final “Absolute Daily Max” for the day. The market is pricing a **0% YES** outcome, which leaves room for a sharp repricing if the official reading lands in a higher temperature band than the crowd currently expects; with settlement tied to the Observatory’s published extract, the key issue is not the citywide “feels like” heat but the single official daily maximum.

The comparison set matters because Hong Kong has already just posted an extreme reading: the Observatory reported **36.9°C** on 9 August 2026, described as the city’s highest ever since records began, while some district stations were even hotter at **39.8°C**. Against that backdrop, the current zero-implied probability looks like a market assuming mean reversion rather than persistence. Historical August normals also point to a very hot baseline: the 1991–2020 daily normal maximum for 10 August is **31.4°C**, but recent Augusts have produced far hotter spikes, including a 2025 daily maximum of **34.4°C** on 10 August.

For traders, the main catalyst is the Observatory’s next official daily extract, which can only settle this contract once the 10 August data are published. Forecast products around the city show highs in the **mid-30s Celsius** range, so the decisive variable is whether cloud cover, showers, or any residual tropical-cyclone influence trims the official maximum below the upper bands. In cross-platform terms, a sportsbook-style weather line would typically be anchored to the forecast high, while a prediction-market price reflects the probability of a specific settlement band; here, the divergence is most likely between a near-zero crowd view and a forecast profile that still leaves meaningful upside to a hotter-than-normal reading.

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Methodology

This page reviews Highest temperature in Hong Kong on August 10? 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 Kalshi vs Polymarket, 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

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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi vs Polymarket trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.