Highest temperature in Guangzhou on July 4?

Platform comparison

Market context

Guangzhou will experience its peak summer heat on 4 July 2026, with the highest temperature recorded at Baiyun International Airport determining the outcome of this prediction contract. The current crowd-implied probability for a "YES" result sits at 0%, yet this figure masks a significant divergence when compared across platforms. While some sportsbook lines suggest a near-certain hit for temperatures above 30°C, the Polymarket frontrunner is 32°C at 34%, with 30°C trailing at 23%[1]. Analyst consensus from the UK Met Office points to a maximum near 31°C, creating a notable gap between the 0% implied probability and the 34% collective view on the leading outcome[1].

Historical climatology frames this probability as highly conservative, given that July is the hottest month in Guangzhou with average daily highs consistently between 33°C and 35°C[4]. WeatherSpark data confirms daily highs average 91°F (32.8°C), rarely dipping below 85°F (29.4°C) or exceeding 96°F (35.6°C)[2]. Previous prediction markets for early July in Guangzhou show similar baselines, where odds below 30°C or above 36°C are deemed improbable, reinforcing that the current 0% YES probability contradicts decades of recorded data where temperatures routinely reach 36°C[3][9].

Traders should monitor real-time updates from Wunderground, the official resolution source, for any sudden shifts in cloud cover or rainfall that could suppress the peak temperature[1]. Recent reports from Xinhua News Agency highlight that Guangzhou has experienced its longest summer since 1961, suggesting a potential for record-breaking heat rather than a cooling anomaly[8]. The China Meteorological Administration’s historical records further indicate that average highs in the 33°C to 35°C range are standard, meaning any deviation below 30°C would be an exceptional outlier rather than a statistical norm[4].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Best Prediction Markets UK, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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.

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 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets UK trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.