Highest temperature in Guangzhou on July 25?

Platform comparison

Market context

Guangzhou's peak temperature on 25 July 2026 will be measured at Baiyun International Airport Station and resolved against historical records from Wunderground. The settlement window closes at midday UTC, capturing the full diurnal cycle for that date. Current crowd pricing reflects genuine uncertainty about which temperature band will contain the day's high, with no consensus forming around any single range.

July represents Guangzhou's hottest month climatologically, with mean daily maxima around 32–34°C and extremes occasionally exceeding 37°C. The city's humid subtropical climate produces consistent heat during this period, though variability exists year-to-year depending on monsoon positioning and upper-level atmospheric patterns. Historical data from Baiyun station shows July peaks typically cluster in the 33–36°C range, with readings above 37°C occurring roughly once every 3–4 years during particularly intense heat episodes.

Traders should monitor mid-July weather pattern evolution and any tropical cyclone activity in the South China Sea, which can suppress temperatures through cloud cover and precipitation. The China Meteorological Administration issues 10-day forecasts that update regularly; significant shifts in monsoon flow or high-pressure system positioning would alter the probability distribution across temperature bands. Sea surface temperatures in the adjacent waters and any developing heat domes across East Asia in late July will be the primary drivers of whether Guangzhou experiences a typical July day or an outlier event.

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 Today. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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.