Highest temperature in Hong Kong on August 5?

Platform comparison

Market context

Hong Kong’s **highest temperature** on 5 August is being priced with a **0% YES implied probability**, so the market is treating the listed outcome set as an extreme longshot unless the day lands squarely in the relevant range. In practical handicapper terms, that makes the consensus strongly bearish on any upside surprise, with the crowd effectively assuming the Observatory’s final “Absolute Daily Max” will sit inside a cooler band than the market’s current YES trigger.

The historical frame is straightforward: August in Hong Kong is usually hot, humid and unsettled, but not uniformly scorching, with long-run August highs typically around **31°C** and forecast ranges this week sitting mostly in the **29°C to 32°C** area. Seasonal guidance from the Hong Kong Observatory says July to September 2026 is expected to be **normal to above-normal** for temperature, while rainfall is slightly more likely to be normal to above-normal, which keeps a plausible contrarian angle alive for a brief heat spike if cloud and showers break late. That said, the favourite remains the more moderate temperature band, and any value on higher outcomes depends on whether traders think the day can deliver a clean afternoon warming rather than the more common damp, capped profile.[1][7][10]

What matters now is the final day-of weather evolution, not the monthly average: the Hong Kong Observatory’s short-range forecast and regional readings will shape whether the day stays under cloud and showers or gets enough sunshine for the maximum to edge higher. BBC and other forecast services are still showing mixed shower and thunderstorm conditions around Hong Kong, which supports the underdog case for lower highs rather than a sharp move into hotter territory.[6][9][15] The real dependency is the Observatory’s eventual published daily extract, since the market cannot resolve until that file appears; traders will be watching for late adjustments to the 9-day forecast, thunderstorm warnings and any typhoon-related disruption, all of which can suppress the ceiling temperature even when the broader seasonal backdrop is warm.[7][9][15]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Who Will Win, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Who Will Win. 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Who Will Win 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.