Highest temperature in Hong Kong on May 31?

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Active sub-markets

Market context

On 31 May 2026, Hong Kong will record its daily maximum temperature, which the Hong Kong Observatory will publish to one decimal place in Celsius. The settlement window closes at noon UTC that day, meaning traders must commit capital before the Observatory's official reading is finalised and archived in its Daily Extract database. The 0% crowd probability reflects either extreme confidence in a specific temperature range or insufficient liquidity to draw meaningful positions; either way, the market awaits deposit inflows to establish genuine price discovery.

Hong Kong's May temperatures cluster between 28–32°C, with historical daily maxima rarely breaching 34°C in that month. The 1951–2020 climate record shows May 31st specifically has seen highs ranging from 26.8°C to 33.5°C, with a median near 30°C. This historical band anchors how traders should weight the current flat probability—it suggests the market has not yet attracted sufficient capital from users depositing via Klarna, SEPA, or USDC to populate the full range of outcome buckets. Shallow order books in weather markets often reflect payment friction rather than genuine forecast disagreement.

Traders should monitor the Hong Kong Observatory's May 2026 weather outlook, typically released mid-month, for any signals of unusual heat or monsoon patterns. Tropical cyclone activity in the South China Sea during late May can suppress temperatures; conversely, high-pressure systems from the north drive heat. The Observatory publishes 9-day forecasts weekly; these updates will likely trigger deposit activity and tighten the probability distribution as settlement approaches. Withdrawal rails matter here—traders holding positions into late May should verify their preferred exit method (Klarna refund, SEPA bank transfer, or USDC redemption) well before the noon UTC deadline.

Methodology

This page is a comparison snapshot: one live quote (Polymarket), four reference venues with their key attributes, and a single execution path — every trade button routes to Polymarket Klarna UK, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

On Polymarket Klarna UK, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket Klarna 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.

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.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.