Highest temperature in Guangzhou on July 23?

Platform comparison

Market context

Guangzhou’s highest temperature is set by the reading at Baiyun International Airport Station, so the key issue is not citywide “feels like” heat but the day’s official airport maximum. At 7:02 UTC, AccuWeather showed Guangzhou at 91°F with a RealFeel of 109°F, which points to a very hot and humid start to the day, but that is not the settlement figure. The crowd is still pricing the contract at 0% YES, while Polymarket’s live book has 36°C as the frontrunner at 47% and 35°C next at 28%, a sharp gap that suggests either stale or thin crowd participation rather than a neutral view of weather risk.[1][2]

Historically, late July is the peak heat season in Guangzhou, with humidity and convective showers often limiting the afternoon high even when the morning is already oppressive. Trip.com’s seasonal guide describes July–August as the hottest period, but also notes that summer rain is frequent and often comes in short, heavy bursts, which can cap the maximum or delay the day’s peak until later in the afternoon.[3] That matters for cross-platform comparison: sportsbook-style pricing on a single temperature band can move quickly with local forecast updates, while a prediction market can lag if traders underweight the chance of a 36°C print despite the strong seasonal setup.

Sources: 1 · 2 · 3

Methodology

We track Highest temperature in Guangzhou on July 23? 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.

Do I need to KYC for this market?

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