Lowest temperature in Hong Kong on August 10?

Platform comparison

Market context

Hong Kong starts the day with a very hot, unsettled set-up: recent forecasts point to thunder with showers and an overnight low around the mid-80s °F, which would be about 29°C rather than anything near a chilly reading. Earlier in the past week, the city also stayed warm, with the lowest temperature in the last 15 days around 76°F, or roughly 24.4°C, so the current crowd-implied 0% YES sits far below what recent conditions have produced.[2][12][17]

That near-zero pricing is easier to read against Hong Kong’s August climate. The Observatory’s 10 August normal minimum is 26.3°C, and August is typically humid and rain-prone rather than cool, with the monthly mean minimum around the high-20s °C in recent climatology tables.[3][11] Historical August readings also show that even a relatively cool day in mid-August tends to settle in the upper 20s °C; for example, past August histories show lows clustered around 27–28°C, not the low-teens or teens that would be needed to threaten some lower temperature bands.[10][18]

For traders, the main catalyst is the Hong Kong Observatory’s final “Daily Extract” for 10 August, because this market cannot resolve until that data is published.[1][5] Intraday weather observations and short-range forecasts matter only insofar as they affect the overnight minimum before the settlement window closes at 12:00 UTC, so the key watch item is whether showers, cloud cover and a weak wind shift keep temperatures elevated rather than allowing a sharper overnight dip.[6][12][17]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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.

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 Prediction Today. 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.

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%.