Highest temperature in Guangzhou on July 21?

Platform comparison

Market context

On 21 July 2026, the highest temperature recorded at Guangzhou Baiyun International Airport Station will determine which range this market resolves to. The settlement window closes at noon UTC on that date, capturing the full calendar day's temperature record from the official monitoring station serving China's southern megacity.

Guangzhou's July climate is consistently hot and humid, with historical highs typically ranging between 33–36°C. The 0% crowd probability suggests either extreme confidence in a specific temperature band or minimal trading activity on this contract. Cross-referencing comparable weather markets on other platforms would reveal whether this reflects genuine consensus or simply thin liquidity. Historical data from Wunderground shows July temperatures in Guangzhou rarely exceed 37°C, though heat waves and tropical systems can produce outliers. The current implied probability divergence warrants scrutiny against seasonal norms and any recent analyst forecasts for Southeast Asian weather patterns in mid-2026.

Traders should monitor China Meteorological Administration seasonal outlooks and tropical cyclone activity in the South China Sea during late June and early July 2026, as these directly influence Guangzhou's peak temperatures. Any significant heat dome formation across southern China or anomalous atmospheric pressure patterns would shift the probability distribution materially. The Baiyun station's official records are the sole arbiter; readings from alternative weather services or unofficial stations carry no weight for settlement purposes. Temperature data becomes locked once the settlement window closes, eliminating any real-time trading advantage after noon UTC on the resolution date.

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 Kalshi vs Polymarket, 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

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.

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.

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.