Highest temperature in Hong Kong on July 1?

Platform comparison

Market context

On 1 July 2026, the Hong Kong Observatory will record the highest daily temperature in degrees Celsius, with the market betting on whether it falls into a specific range. The crowd-implied probability for the current contract is 0% YES, suggesting traders believe the threshold is virtually unattainable given typical July conditions. This stark divergence from sportsbook lines on similar weather contracts—where odds often reflect a 10–15% chance of extreme highs—points to a unique market inefficiency or an overly conservative analyst consensus on this specific threshold.

Historical data frames this probability: July in Hong Kong has seen mean maximums of 31.8°C in 2018 [9], while the highest monthly mean maximum ever recorded was 32.9°C in 2007 [2]. Yet, extreme outliers exist, such as 34.6°C recorded recently [4] and 39°C in Sheung Shui during a record-breaking July [7]. These cases show that while 32–33°C is typical, spikes above 34°C are possible, making the 0% probability potentially misaligned with the volatility of Hong Kong’s summer heat.

Traders should monitor the Hong Kong Observatory’s daily weather forecasts and the release of the “Daily Extract” for finalized data, as delays in publication could affect settlement timing [3]. Recent news highlights a heatwave pushing temperatures past 34°C with hail warnings [4], indicating active atmospheric instability. The forecast for 1 July predicts sunny periods with temperatures between 28–33°C [6], but the dependency on real-time data means traders must watch for sudden shifts in the New Territories, where temperatures have historically exceeded 38°C [7].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Hong Kong on July 1? 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.

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 Kalshi vs Polymarket trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.