Highest temperature in Hong Kong on July 10?

Platform comparison

Market context

On 10 July 2026, Hong Kong will record its daily absolute maximum temperature, a real-world event that determines the settlement of this prediction market. The crowd-implied probability for the highest temperature falling into the upper range is currently 0% YES, suggesting the consensus expects a moderate peak well below record-breaking levels. This stark valuation contrasts with historical precedents where July has frequently delivered extreme heat.

Historically, July is Hong Kong’s hottest month, with the city experiencing its highest monthly maximum temperatures often exceeding 35°C. In July 2022, Hong Kong recorded its hottest month since records began in 1884, breaking the previous record set in July 2020[1]. The ranking of air temperature in July shows the highest monthly maximum temperature reached 35.7°C between 1885 and 2019[2]. Current forecasts for July 2026 indicate daily highs ranging from 86°F to 93°F (approximately 30°C to 34°C), with an average high of 89°F (32°C)[3]. Recent data from late June 2026 shows a peak of 91.6°F (33.1°C), while the lowest temperature in early July was 78.2°F (25.7°C)[4]. The 0% probability may be an underdog play, as the historical tendency for July to produce record heat suggests value could lie in betting against the consensus if a heatwave develops.

Traders should monitor the Hong Kong Observatory’s daily weather updates and any announcements regarding tropical cyclones or monsoon surges, which can significantly alter temperature outcomes. The settlement depends on the finalisation of the “Daily Extract” data, which is only published after the date’s information is finalized[7]. Recent news from China Daily highlights that July has been the hottest month of Hong Kong on record, reinforcing the potential for extreme temperatures[5]. Watch for any sudden shifts in the forecast, as the current 0% implied probability may not account for the possibility of a late-July heat spike that could push temperatures into the upper range. The value spot likely sits in contrarian positions betting on a higher peak, given the historical pattern of July delivering record-breaking heat.

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

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 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.

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.

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.