Highest temperature in Hong Kong on July 4?

Platform comparison

Market context

The real-world event hinges on the absolute daily maximum temperature recorded by the Hong Kong Observatory on 4 July 2026, measured in degrees Celsius to one decimal place. This figure will determine which temperature range the prediction market resolves to, with the settlement window closing at 12:00 UTC on 4 July 2026. The market currently shows a 0% implied probability for the “YES” outcome, suggesting the crowd expects the temperature to fall outside the specified range.

Historically, July is Hong Kong’s hottest month, with average highs around 31.7°C (89°F) and recorded peaks reaching 35.7°C in 2018[6]. Recent forecasts for July 2026 indicate daily highs between 30°C and 35.5°C (86°F–96°F), with overnight lows near 26.7°C–27.8°C (79°F–82°F)[1]. Visual Crossing data shows a peak of 33.3°C (92.1°F) on 2 July 2026, just two days prior[5]. These comparable cases frame the 0% probability as potentially premature, given the region’s consistent heat during this period.

Traders should monitor the Hong Kong Observatory’s Daily Extract for finalized data, as resolution cannot occur until publication[4]. Key catalysts include tropical cyclone activity, monsoon shifts, and urban heat index announcements, all of which can spike temperatures. The Observatory recently confirmed July 2025 as the city’s hottest month on record, with the highest number of hot days since 1884[9]. Programmatically, bots should track the Observatory’s climatological feed and trigger conditional orders once the Daily Extract is updated, ensuring execution before the settlement deadline.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on July 4? 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 Polymarket Bot UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 Polymarket Bot 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.