Highest temperature in Guangzhou on July 31?

Platform comparison

Market context

Guangzhou’s airport temperature needs only a modest overshoot of the city’s July norm to settle a **YES** at the higher bands, but the market is currently pricing that outcome at **0%**, which is a clear divergence from the weather outlook. July in Guangzhou is typically hot and humid, with average highs around 33–34°C and occasional peaks into the mid-30s Celsius, while current forecast sources for 31 July point to daytime highs around 34–37°C rather than anything extreme enough to justify an outright zero on the upper ranges.[1][2][3][5][20]

Historically, late-July Guangzhou readings often sit close to the annual summer ceiling rather than far below it, so the key question is not whether it will be warm, but whether the Baiyun Airport station records a brief spike above the main forecast band. WeatherSpark shows July daily highs in Guangzhou commonly around 91°F, rarely exceeding 96°F, which keeps the highest-temperature contract sensitive to small differences between city-wide forecasts and the airport’s actual reading.[11] That makes the current implied probability look notably lower than the published weather expectations, and also below the sort of analyst-style consensus one would infer from the mainstream forecast set, which clusters around low-to-mid 30s Celsius rather than a cool day.[1][4][7]

For traders, the main catalysts are the day’s heating profile, cloud cover, showers and thunderstorms, and any humidity-driven RealFeel-style uplift that may or may not translate into the actual airport maximum. AccuWeather’s minute and daily forecasts already show warm early-morning conditions and no immediate precipitation in the short term, while other services flag thundery showers and high rain probability later in the day, which could cap the maximum if they arrive early.[2][12] The settlement source is Wunderground’s historical daily page for Guangzhou Baiyun International Airport, so the live station observation pattern through the afternoon local time will matter more than city-level forecasts alone.[8]

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

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 Best Prediction Markets 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.

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.