Highest temperature in Hong Kong on July 9?

Platform comparison

Market context

The real-world event at the heart of this market is the peak heat recorded across Hong Kong on 9 July 2026, measured in degrees Celsius by the Hong Kong Observatory. In prediction markets, a YES share means you believe the outcome will fall within the specified temperature range, while a NO share means you expect it to fall outside that range. This particular market resolves to the range containing the highest temperature recorded as the "Absolute Daily Max" once the Observatory finalises its Daily Extract data.

Historical July data frames how to interpret the current 0% YES probability. The Observatory’s 30-year records show July’s highest monthly maximum reaching 35.7°C, with recent years seeing daily peaks of 34.6°C and even 36.1°C breaking the 1963 record [3][5]. A recent heatwave pushed temperatures to 39°C in Sheung Shui, illustrating that extreme highs are possible [7]. Given these comparable cases, the 0% probability suggests the market expects the temperature to miss the specific range entirely, likely because forecasters anticipate a lower peak or a different range bucket.

Traders should monitor the Observatory’s Daily Extract publication schedule, as the market cannot resolve until data is finalized [8]. Watch for official heatwave announcements or weather summaries for 2026, which may signal whether record-breaking conditions are expected [4]. The Hong Kong Observatory’s climate change data indicates temperatures are rising by 0.35°C per decade, a trend that could influence July 2026 outcomes [10]. No moralising is needed on whether to trade; the facts show the market hinges on when the Observatory releases its verified maximum temperature.

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

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.

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.

Do I need to KYC for this market?

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

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.