Highest temperature in Hong Kong on May 31?

Platform comparison

Active sub-markets

Market context

On 31 May 2026, the Hong Kong Observatory will record the day's highest temperature in degrees Celsius. This market resolves to whichever temperature band contains that single daily maximum reading, sourced from the Observatory's published Daily Extract data. The settlement window closes at 12:00 UTC on that date, though resolution itself cannot occur until the Observatory finalises and publishes the temperature record, typically within days of the observation date.

Historical May temperatures in Hong Kong show considerable variation. The Observatory's climate records indicate May daily maxima typically range between 28°C and 33°C, with occasional excursions higher during early-season heat waves. The current 0% crowd probability suggests traders are either awaiting clearer market definition or treating this as a placeholder pending range specification. Comparable weather markets on prediction platforms show that seasonal temperature forecasts become more reliable within two weeks of the event; currently, May 2026 sits beyond most meteorological forecast horizons, explaining the absence of meaningful probability distribution.

From a regulatory standpoint, this market operates under different frameworks depending on trader location. The German GlüStV (Glücksspielstaatsvertrag) treats prediction markets as gaming products requiring specific licensing; UK-domiciled platforms typically fall under FCA oversight rather than gambling regulation. US CFTC reach extends to derivatives on weather indices, though binary prediction markets occupy a grey zone depending on whether they're classified as gaming or financial instruments. The "no-KYC up to $1,500" threshold common in some prediction market jurisdictions would apply here as a single-event weather contract, meaning traders below that stake level may access the market with minimal identity verification in certain regulatory zones, though platform-specific terms always supersede general guidance.

Methodology

This page reviews Highest temperature in Hong Kong on May 31? across five venues. We show live odds for Polymarket-based markets (sourced from the Polygon order book); for other venues we list platform attributes, since the comparable contracts are not exposed via a public API on every venue. Every CTA points at Polymarket Legal UK — the application we operate, where you trade directly against the Polymarket order book at 0% fees.

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 Legal UK is available in most jurisdictions where Polymarket isn't directly accessible. Polymarket itself is geo-blocked in the US/UK/EU. Always check local regulations.

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 it cost to trade on Polymarket Legal UK?

Zero. Polymarket Legal UK routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.