Highest temperature in Hong Kong on July 1?

Platform comparison

Market context

Hong Kong is entering its peak summer heat today, with July 1 marking the start of the month that historically delivers the highest temperatures in the region. The crowd-implied probability of 0% for any specific temperature range reflects a market that has not yet settled on a definitive outcome, likely due to the inherent volatility of daily extremes in a typhoon-prone season. Historical data confirms July is the hottest month, with average highs around 32°C and occasional spikes to 34°C, while the 2026 forecast suggests daily highs ranging from 28°C to 33°C, making any single range a precarious bet without further climatic confirmation[2][4][5].

Traders should closely monitor the Hong Kong Observatory’s seasonal forecast for July–September 2026, which is scheduled for release around 1 July 2026 and will clarify whether temperatures will be above-normal due to the developing El Niño event[3]. The continued rise in sea surface temperatures in the equatorial Pacific, now above normal since April 2026, is expected to push Hong Kong’s summer temperatures higher, a trend that has been significant over the long term[3]. Additionally, watch for typhoon activity, as storms passing south of Hong Kong can cause unbearably hot conditions with light winds, while closer approaches bring torrential rain that suppresses temperatures[4]. The resolution depends entirely on the finalized "Daily Extract" data from the Observatory, which will record the absolute daily maximum to one decimal place once published[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.

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.

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.