Highest temperature in Hong Kong on July 7?

Platform comparison

Market context

Hong Kong’s July 7 high-temperature market has collapsed to 0% YES after a sharp overnight shift in trader positioning, with the crowd now overwhelmingly backing 30°C as the frontrunner at 40% probability, followed by 29°C at 24% [2]. This realignment reflects a rapid reassessment of near-term heat risk, moving away from earlier low-temperature bets that previously dominated sentiment.

Historical July data frames this probability shift: the first ten days of July typically see average highs of 29.7°C, with lows around 26.2°C, while the broader month averages 29.6°C highs [10]. The Hong Kong Observatory’s seasonal outlook, updated as of 30 June 2026, forecasts normal-to-above-normal temperatures for July–September, driven by rising equatorial Pacific sea surface temperatures and an emerging strong El Niño expected by late summer [4]. This long-term warming trend, combined with monsoon moisture patterns, supports the market’s current tilt toward 30°C rather than cooler outcomes.

Traders should monitor the Hong Kong Observatory’s Daily Extract for the “Absolute Daily Max (deg. C)” once finalized, as this is the sole resolution source [2]. Key catalysts include any official El Niño intensity updates from climate models and real-time tourist weather bulletins, which currently show a 27–31°C range for 6–7 July with medium-high rain probability [5]. AccuWeather’s July 2026 forecast also projects daily highs between 86°F and 95°F (30–35°C), reinforcing the 30°C cluster as the most plausible outcome [3].

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

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 Prediction Today. 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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

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.