Highest temperature in Hong Kong on July 5?

Platform comparison

Market context

Hong Kong faces a day of mainly cloudy skies with severe squally thunderstorms and a few showers, as Tropical Cyclone Maysak weakens inland while an active southerly airstream keeps conditions unsettled[2]. The 0% crowd-implied probability for a record-high temperature reflects this immediate disruption, as heavy rain and cloud cover suppress the intense solar heating required to push temperatures toward the upper end of July’s typical range[2].

Historically, July in Hong Kong sees average highs near 32°C, with record peaks often occurring during clear, hot spells driven by subsiding air from distant cyclones like Bavi[4]. In comparable years, days with severe thunderstorms and high humidity rarely exceed 31°C, making the current 0% probability for a top-tier heat day consistent with past patterns where unsettled weather capped maximum temperatures[2][4].

Traders should monitor the Hong Kong Observatory’s 9-day forecast updates for shifts in cloud cover and the arrival of Bavi’s subsiding air, which could bring fine, very hot weather midweek[2]. The key dependency is the finalisation of the “Daily Extract” data for 5 July 2026, which will confirm the absolute daily maximum temperature to one decimal place[3]. Recent seasonal forecasts indicate normal to above-normal temperatures for July–September due to an emerging El Niño, but today’s stormy outlook remains the dominant short-term factor[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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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.

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 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Prediction Today 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.