Highest temperature in Hong Kong on June 20?

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Active sub-markets

Market context

Polymarket is pricing this Hong Kong temperature contract at **0% YES** today, which means the market is effectively saying there is no live bid for a highest daily maximum that lands in the YES settlement band. For traders using USDC on Polygon, that is a thin but informative signal: the conditional tokens imply the crowd sees little value in paying up for a hotter-than-expected outcome, even though settlement will ultimately follow the Hong Kong Observatory’s final “Absolute Daily Max” for 20 June once the daily extract is published.

For context, Hong Kong’s June climate is already hot and humid, with typical summer temperatures in the high 20s to low 30s Celsius, and the Observatory’s June–August 2026 seasonal outlook calls for **above-normal temperature** overall.[1][2] That said, seasonal warmth does not guarantee an extreme daily maximum: the market is about the single highest reading for the day, not the average, and Hong Kong’s coastal setup means cloud, rain and sea breeze can cap the afternoon high. As a result, a 0% price is less a statement that Hong Kong will be cool than a signal that traders think the available temperature ranges are not currently offering a believable path into the relevant YES range.

A Polymarket user should watch the Observatory’s short-range updates, the tourist weather page and the final Daily Extract release, because those determine whether a late surge in heat or a wetter, cloudier pattern dominates the official maximum.[4][8] The key dependency is timing: the market cannot resolve until the 20 June data is finalised, and the venue’s own temperature readouts already show the day’s conditions are being tracked in real time at the Observatory site.[4][8] If the latest forecast or observed readings stay around the low 30s Celsius rather than pushing materially higher, the current 0% print is likely to persist.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on June 20? on the five venues with material liquidity for prediction markets. Live odds come from the Polymarket Polygon order book — the only source that ships real-time data under an open licence. For Kalshi, Betfair and Manifold we list platform attributes (fee, KYC, settlement, payment) instead of fabricated odds, because their APIs use non-comparable contract definitions.

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 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.

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 does it cost to trade on Polymarket UK?

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

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, Polymarket UK triggers a quick verification flow that finishes in 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.