Highest temperature in Hong Kong on July 28?

Platform comparison

Market context

The Hong Kong Observatory will record the highest temperature in Hong Kong on 28 July 2026, measured to one decimal place in degrees Celsius. This market resolves based on the absolute daily maximum temperature published in the Observatory's Daily Extract once data is finalised. The settlement window closes at midday UTC on that date, though resolution may be delayed pending official publication.

Hong Kong's July temperatures cluster tightly around established seasonal norms. Historical records show daily maxima in late July typically range between 32–34°C, with extremes occasionally reaching 35–36°C during heat waves. The 0% implied probability suggests the crowd expects no outlier conditions—a reasonable baseline given that temperatures above 37°C on any single July day remain statistically uncommon, occurring perhaps once per decade. The consensus treats this as a straightforward seasonal weather event with limited surprise potential.

Traders should monitor the Asian summer monsoon pattern and any tropical cyclone activity in the weeks preceding late July 2026, both of which can suppress or elevate temperatures. The Observatory publishes extended forecasts roughly ten days ahead; these will provide the first concrete signals of whether late-July conditions favour typical seasonal ranges or anomalous heat. El Niño or La Niña conditions active in mid-2026 could shift baseline expectations, though such shifts typically move markets gradually rather than creating sharp repricing near settlement. The absence of any significant current probability mass suggests limited market engagement, potentially leaving value uncaptured if seasonal drivers shift unexpectedly.

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 Who Will Win 2026. 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.

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.