Highest temperature in Hong Kong on July 24?

Platform comparison

Market context

Hong Kong’s on-chain temperature contract is pricing **0% YES** on Polymarket, with USDC locked into conditional tokens on Polygon and settlement tied to the Hong Kong Observatory’s final “Absolute Daily Max” for 24 July. That zero bid implies the market sees essentially no chance of the resolved temperature landing in the YES range, rather than saying anything about the weather itself.

For context, Hong Kong in July is a hot, humid, and often rainy climate, with typical monthly rainfall around 296.1 mm and roughly 31 rainy days, so the city can still post a high daytime maximum even in an unsettled pattern.[1] For a market like this, the practical reference point is not whether the day feels oppressive, but where the Observatory’s one-decimal Celsius reading ultimately falls once the daily extract is finalised.

The main catalysts for traders are the Observatory’s day-by-day updates, the timing of the daily extract publication, and any shift in the wider monsoon or tropical-cyclone pattern that could cap or lift the afternoon maximum. Because settlement cannot happen until the Hong Kong Observatory publishes the final data, the last hours before and after the 12:00 UTC window can matter less than the official release itself, which is the binding source for resolution.[1]

Sources: 1

Methodology

We track Highest temperature in Hong Kong on July 24? 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

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.