Highest temperature in Hong Kong on May 31?

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Market context

The Hong Kong Observatory will record the highest daily maximum temperature on 31 May 2026, measured in degrees Celsius to one decimal place. This market resolves based on the official "Absolute Daily Max" figure published in the Observatory's Daily Extract once data is finalised following the settlement window closure on 31 May at 12:00 UTC.

May temperatures in Hong Kong typically range between 28–32°C, with the month marking the transition into the pre-monsoon season. Historical data from the Observatory shows that late May daily maxima rarely exceed 33°C in the territory, though occasional heat spikes can push readings toward 34–35°C during particularly warm years. The 0% crowd probability suggests traders expect the market to resolve within a standard range rather than an extreme outlier scenario. Comparable May 31st readings from recent decades provide the baseline: most years cluster in the 29–31°C band, with outliers requiring unusual atmospheric conditions.

Traders should monitor the broader weather pattern developing in late May 2026, particularly any ridge of high pressure or tropical air mass positioning across southern China. The Hong Kong Observatory issues regular forecasts and advisories that may signal elevated temperatures weeks in advance. Any official heat warnings issued in the days preceding 31 May would indicate conditions favouring higher temperature ranges. The Observatory's published forecast data, updated daily on its website, will be the primary signal for assessing probability shifts as the date approaches.

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 Sport Prediction — 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?

Sport Prediction 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 Sport Prediction?

Zero. Sport Prediction 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.