Highest temperature in Guangzhou on July 23?

Platform comparison

Market context

Guangzhou is already running hot, with current conditions around 33°C and a RealFeel near 43°C, so the day starts from a level that could still support a high maximum even if cloud and showers interrupt the climb.[1] In this market, a **YES** share pays out if the day’s highest recorded temperature at Guangzhou Baiyun International Airport Station lands inside the market’s target range; a **NO** share pays if it lands elsewhere, using the Wunderground daily history page as the settlement source.

For readers new to prediction markets, the current 0% YES price means traders collectively assign almost no chance to the chosen temperature band. That does not mean the outcome is impossible; it means the market is effectively saying the observed high is expected to fall outside that range. In Guangzhou, July and August are the hottest months, and the city also has a humid, rain-prone summer pattern, so short-lived downpours can cap the peak even on an otherwise oppressive day.[2]

The main catalysts are local weather developments rather than policy or event schedules: midday cloud cover, thunderstorm timing, and whether the airport station gets a brief dry, sunny window before the maximum is set. Because the settlement window ends at 12:00 UTC, traders should focus on how the temperature evolves through the late morning in Guangdong, when heat usually builds fastest and convective rain can either suppress or delay the day’s top reading.[1][2]

Sources: 1 · 2

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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Market UK. 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.

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.

Do I need to KYC for this market?

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