Highest temperature in Hong Kong on June 30?

Platform comparison

Market context

The Hong Kong Observatory is tracking whether the highest temperature recorded on 30 June 2026 will fall into a specific range, with the market currently implying a 12% chance for the "YES" outcome. Historical data shows that June highs in Hong Kong typically average near 30–31°C, with daily peaks ranging from 86°F to 91°F (30–33°C), while the absolute maximum for June in recent decades reached 35.6°C [3][4]. The seasonal forecast for June–August 2026 indicates above-normal temperatures across Hong Kong, driven by ENSO conditions and climate models, suggesting a higher likelihood of extreme heat events than usual [3][7].

Traders should monitor the Hong Kong Observatory’s "Daily Extract" publication schedule, as the market cannot resolve until the "Absolute Daily Max (deg. C)" is finalized and published [5]. Recent warnings from the Observatory highlight extreme heat risks in the New Territories, with temperatures expected to hit 37°C on specific days, underscoring the volatility in near-term forecasts [8]. The divergence between Polymarket’s implied probability (44% for 31°C, 60% for 32°C) and the broader 12% "YES" crowd-implied probability suggests a meaningful gap in how different platforms interpret the same contract, with Polymarket traders leaning more heavily toward higher temperature ranges [1][2]. Analyst consensus, based on the seasonal forecast, aligns with the above-normal temperature trend, reinforcing the need to watch real-time updates from the Observatory for any shifts in the forecast [3][7].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

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

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

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is PolyGram. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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.

Do I need to KYC for this market?

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