Highest temperature in Hong Kong on August 19?

Platform comparison

Market context

The Hong Kong Observatory will record the highest temperature in Hong Kong on 19 August 2026, measured to one decimal place in degrees Celsius. This market resolves based on the absolute daily maximum temperature published in the Observatory's Daily Extract dataset, with settlement occurring once official data is finalised and released.

August in Hong Kong typically sees daily maxima between 31°C and 34°C, though extremes have occasionally pushed higher. The territory's record August high stands at 36.3°C, set in 1967. More recent August data shows the Observatory recording temperatures above 35°C roughly once per decade during this month, with most years clustering in the 32–34°C band. The 0% crowd probability suggests traders are either awaiting clearer seasonal forecasts or treating this as a placeholder market pending meteorological input closer to the date.

Traders should monitor the Asian summer monsoon patterns and any developing heat systems in the weeks preceding mid-August 2026. The Hong Kong Observatory publishes extended-range forecasts and seasonal outlooks that typically become more refined 2–3 weeks ahead. El Niño or La Niña conditions, if present, would influence regional temperature patterns. The settlement window closes at midday on 19 August, allowing only morning temperature data to count; any afternoon spike would not affect resolution. Historical volatility in August temperatures suggests meaningful probability should attach to ranges above 34°C, particularly if early-month data shows sustained heat building across the region.

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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

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.

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'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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Who Will Win 2026 trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.