Highest temperature in Hong Kong on July 1?

Platform comparison

Market context

Hong Kong’s official daily maximum temperature on 1 July 2026 is the real-world event this market resolves, with the Hong Kong Observatory’s “Absolute Daily Max” in degrees Celsius serving as the definitive source. On Polymarket today, the contract prices the 33°C range at 55% implied probability, while the 0% YES probability for any outcome below 31°C reflects tight trader consensus clustering around 31–33°C. This pricing ignores abstract climate theory and instead mirrors on-chain mechanics: USDC stakes on Polygon, conditional tokens locking in exposure, and the market’s sharp 21.5% overnight repricing toward 33°C as liquidity flows in [1][3].

Historical July climatology frames this current probability, with Hong Kong’s warmest months (late May to mid-September) averaging 33°C daytime highs under prevailing southwesterly flow [5]. The Hong Kong Observatory’s seasonal forecast for July–September 2026 projects normal to above-normal temperatures, consistent with long-term warming trends and typical early-July conditions where daily highs rarely dip below 31°C absent unusual synoptic influences [4][9]. Past data shows July mean maximums hovering near 32°C, with the 28°C–33°C range capturing most recorded extremes, making the 0% probability for lower ranges statistically sound given seasonal warmth [2][10].

Traders should monitor the Observatory’s “Daily Extract” publication schedule, as resolution cannot occur until the finalized data for 1 July appears in the relevant extract [1]. Key catalysts include the Observatory’s monthly forecast updates for July 2026, which may signal shifts in rainfall or temperature anomalies, and real-time synoptic influences like tropical depressions that could suppress highs [9]. Recent weather outlooks for south China note temperature volatility, with some forecasts predicting drops to 13°C under unusual conditions, though such events remain rare in July [6]. The market’s dependency on official data finalisation means liquidity may surge only once the extract is published, aligning with USDC settlement mechanics on Polygon [1].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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

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.

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 Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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.