Highest temperature in Hong Kong on July 7?

Platform comparison

Market context

On 7 July 2026, Hong Kong will record its daily maximum temperature, a single real-world metric that determines the outcome of a prediction market on whether the peak heat exceeds a specific threshold. The current crowd-implied probability of 0% for a "YES" outcome suggests traders are virtually certain the temperature will stay below the required level, yet this stance diverges sharply from historical patterns and official forecasts.

Historical data frames this probability as unusually conservative. The Hong Kong Observatory’s seasonal forecast for July–September 2026 predicts normal to above-normal temperatures, citing the latest ENSO status and climate models [1]. Recent records show July 2026 was the city’s hottest month on record, with daytime peaks reaching 33°C and 34.6°C [7][8]. Average July highs typically range from 86°F to 95°F (30°C to 35°C), making a sub-threshold result statistically improbable [3]. While a competing market on low temperatures rates 27°C as the most likely single outcome with 40% probability, the 0% implied probability here ignores the strong trend of abnormally high heat [2][5].

Traders should monitor the Hong Kong Observatory’s "Daily Extract" for the finalized "Absolute Daily Max" reading, which is the sole resolution source [4]. No immediate catalyst announcements are pending, but the settlement window closes on 7 July 2026 at 12:00 UTC, requiring data publication before resolution. The Observatory’s recent confirmation of abnormally high temperatures in 2026, including 28°C highs on 14 consecutive days, reinforces the likelihood of elevated peaks [5]. Analyst consensus on similar contracts often aligns with the 30°C+ average, suggesting the 0% probability may reflect a mispricing rather than a genuine meteorological shift.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on July 7? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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 Kalshi vs Polymarket. 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 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.