Lowest temperature in Hong Kong on August 5?

Platform comparison

Market context

Hong Kong’s overnight low has been sitting in the high-20s, and the market’s 0% YES pricing on a colder outcome reflects that the last 24–48 hours of guidance have not pointed to any meaningful cooling risk. Polymarket’s own market page says the leading outcome is **27°C** at about **96%**, with **26°C** a distant second, and it cites official forecasts and supporting model guidance projecting a minimum of **27°C** under typical summer monsoon conditions, with light winds, high humidity and isolated showers limiting overnight cooling.[1]

That framing is consistent with Hong Kong’s August climatology: the Hong Kong Observatory’s 1991–2020 normal for **5 August** shows a mean minimum of **26.8°C**, which makes a 27°C floor a very ordinary result for this point in the season.[3] The historical record also shows that lower minima on 5 August tend to need heavy rain or broader disturbance, as in **2025** and **2020**, when rain-cooled conditions pulled the Observatory minimum down to **24.0°C** and **24.9°C** respectively.[2][9]

What matters now is whether late-day showers or a stronger-than-expected monsoon surge develop before the Observatory’s daily extract is finalised. The settlement source is the Hong Kong Observatory’s published **“Absolute Daily Min (deg. C)”** in the relevant Daily Extract, and the market notes that later revisions to initially published temperatures will not count.[11][1] Traders should therefore watch the Observatory’s overnight and early-morning updates, any shift in rainfall timing, and the final posting of the daily climatological data, rather than intraday temperature chatter.[6][11]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Lowest temperature in Hong Kong on August 5? 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

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.

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.

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.

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%.