Highest temperature in Hong Kong on August 9?

Platform comparison

Market context

Hong Kong has already started the day **very hot**, with the Observatory reporting **31°C at 4 a.m. HKT** and forecasting persistently hot conditions through the day. That leaves the settlement firmly dependent on how much heating builds after sunrise, rather than on anything already locked in early this morning.[9][2]

The market is best read against Hong Kong’s August norm, where the Observatory’s climatology for 9 August shows a daily normal maximum of **31.6°C** at the reference station, so a finish in the mid-30s would be a material departure from average. Recent HKO reporting also shows how quickly these setups can run hot: in 2024, the city saw a spell from 3 to 9 August with the Observatory reaching **35.4°C** on 5 August, the month’s high.[5][3]

For traders, the key catalysts are the Observatory’s daytime updates, any shift in cloud cover or wind, and whether convection or sea-breeze effects cap the peak before mid-afternoon. Private forecasts are already pointing to an unusually hot day, with one model-based outlook showing around **36°C** for Hong Kong today and an AccuWeather forecast near **100°F**; if those readings verify, the market’s lower temperature bands look vulnerable.[8][12]

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 Prediction Today, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

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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.

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.

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%.