Highest temperature in Hong Kong on July 1?

Platform comparison

Market context

The real-world event in question is the highest temperature recorded by the Hong Kong Observatory on 1 July 2026, measured in degrees Celsius to one decimal place. Current crowd-implied probability for any specific temperature range hitting this mark sits at 0% YES, suggesting traders view the contract as either mispriced or lacking a clear catalyst for resolution at this moment.

Historical data frames this near-zero probability as an outlier when compared to typical July extremes. The Hong Kong Observatory recorded a monthly mean maximum of 32.9°C in July 2007, while July 2024 saw peaks of 34.8°C, and recent reports indicate temperatures soaring past 34.6°C with a record-breaking 36.1°C observed earlier this year[2][3][4][9]. In contrast, a separate prediction market on Lines.com assigns a 44.5% chance that the daily minimum hits exactly 28°C, highlighting a stark divergence in trader confidence between low and high temperature contracts[1].

Traders should monitor the Hong Kong Observatory’s "Daily Extract" for finalised "Absolute Daily Max" data, as the market cannot resolve until this official publication occurs[5]. Recent news from the South China Morning Post confirms an active heatwave with hail warnings issued, suggesting volatile conditions that could push temperatures higher than forecast[3]. AccuWeather forecasts July 2026 highs between 85°F and 93°F (roughly 29.4°C to 33.9°C), but the active heatwave may invalidate these models, making the 0% implied probability a potential mispricing if the heat persists[8]. The settlement window ends 12:00 UTC on 1 July 2026, requiring immediate data verification once the observatory releases its figures[5].

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

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

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.

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.