Highest temperature in Hong Kong on July 12?

Platform comparison

Market context

The Hong Kong Observatory will record the absolute daily maximum temperature in degrees Celsius for 12 July 2026, which determines the settlement of this weather contract. Today, Polymarket prices the YES outcome at 0%, implying the crowd believes the temperature will fall outside the specific range offered, despite July being historically Hong Kong’s hottest month [1].

Historical data shows July frequently breaks heat records, with the month recently becoming Hong Kong’s hottest ever by shattering 11 hot-weather benchmarks [1]. The highest monthly maximum temperature recorded in July since 1885 reached 35.7°C, while average July highs typically sit around 31.8°C to 32.2°C [2][9]. Recent 2026 forecasts for Sha Tin indicate daily highs ranging from 30°C to 34°C (86°F to 94°F), suggesting the current 0% probability may overlook the likelihood of extreme heat on this specific date [3].

Traders must monitor the Hong Kong Observatory’s “Daily Extract” for the finalized “Absolute Daily Max” figure, as the market cannot resolve until this official data is published [1]. The settlement depends entirely on the Observatory’s confirmation, with no alternative resolution sources accepted. Given the recent trend of record-breaking July temperatures, the 0% implied probability appears disconnected from the climatic reality of Hong Kong’s peak summer season [1]. Watch for any official heatwave announcements or extreme weather bulletins issued by the Observatory before the 12:00 UTC settlement deadline.

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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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.

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.

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.