Highest temperature in Hong Kong on August 9?

Platform comparison

Market context

Polymarket prices this contract at **0% YES** right now, so the on-chain market on Polygon is effectively saying it does not expect the Hong Kong Observatory’s highest reading on 9 August 2026 to land in the YES range. For a trader holding USDC-backed conditional tokens, that means the current order book is treating any qualifying outcome as vanishingly unlikely, even though the market cannot settle until the Observatory publishes the finalized “Absolute Daily Max (deg. C)” in its Daily Extract.

That reading sits against a Hong Kong August climatology that is already hot enough to keep a non-zero tail risk in play. The Observatory’s long-run daily normal for 9 August shows a mean maximum around the low 30s Celsius, with typical daytime peaks well into the 30s and humid conditions common in late summer.[6] Recent summers have also delivered extreme spikes: the Hong Kong government highlighted August as exceptionally hot in 2024,[4] while reports in 2026 described the city’s hottest day of the year so far, with the Observatory at 34.7°C and some districts above 35°C.[13][20]

The key catalysts for this market are the Observatory’s morning-to-afternoon update cycle, any heat-related warnings, and whether a hotter inland or urban reading appears before the day closes. Polymarket traders should watch the HKO hourly readings and final daily extract rather than generic forecasts, because settlement depends on the official Observatory maximum, measured to one decimal place in Celsius.[2][10] Forecast services already point to a very warm day in Hong Kong, with highs around the mid-30s Fahrenheit-equivalent range and conditions described as cloudy to very hot.[1][9]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Hong Kong on August 9? 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 PolyGram, 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 PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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.

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.