Highest temperature in Guangzhou on July 21?

Platform comparison

Market context

Guangzhou will record its peak daily temperature on 21 July 2026, measured at Baiyun International Airport Station and settled via Wunderground historical data in Celsius. The market currently shows 0% implied probability across all temperature bands, suggesting either incomplete crowd participation or uncertainty about which range will contain the actual high. Settlement occurs at 12:00 UTC on that date, giving traders a defined window to monitor real-time weather reporting before final resolution.

Guangzhou's July climate is consistently hot and humid, with historical highs typically ranging between 32–36°C during mid-summer. The city's 30-year average peak temperature for July sits around 33–34°C, though extremes have occasionally pushed toward 37–38°C during heat waves. Reviewing Wunderground's historical records for prior 21 July observations at this station provides the most reliable baseline; traders should cross-reference multiple years to assess the probability distribution across the market's temperature bands and identify which ranges carry genuine edge versus crowd indifference.

Catalysts affecting the outcome include tropical weather systems and monsoon patterns active across southern China in July. The China Meteorological Administration publishes 10-day forecasts and heat alerts that typically become more precise 5–7 days ahead of the settlement date. Traders should monitor these official forecasts alongside regional news coverage from outlets such as Xinhua or local Guangzhou media for any unusual atmospheric conditions—El Niño or La Niña phases can influence summer temperatures across the region. The settlement mechanism's reliance on a single airport station means localised weather variations matter; any equipment issues or data gaps at Baiyun would require Wunderground's fallback procedures, which should be reviewed before committing capital.

Methodology

Methodologically this overview focuses on on-chain pricing: Polymarket's live mid comes from the Polygon conditional-token order book and settles automatically in USDC. The other three venues — Kalshi, Betfair, Manifold — sit alongside as off-chain reference points so you can see how the contract translates across regulatory and settlement regimes.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

FAQ

What are crypto prediction markets?

Crypto prediction markets are on-chain smart contracts where you buy YES or NO shares on a future crypto event (e.g. "BTC above $100k by year-end"). The market price between 0¢ and 100¢ is the implied probability.

What does a transaction cost on Polygon?

Polygon gas is typically under $0.01 per transaction. A full trade cycle (Approve + Order + Fill) totals around $0.03 — compared to $5-50 on Ethereum mainnet.

How does UMA secure the resolution?

The UMA Optimistic Oracle uses a bond system: a proposer posts a bond, a two-hour challenge window opens. On dispute the losing side forfeits the bond — financial incentive for honest resolution.

How volatile are crypto prediction markets?

Crypto markets react to spot prices — a 5% BTC move typically shifts a "BTC above X by date" market 10-20%. Polymarket crypto market liquidity is usually six-figure USD, sufficient for active trading.

Which crypto markets exist on Polymarket?

Currently active markets include BTC/ETH/SOL price targets, halving dates, ETF approvals, hard-fork outcomes and Layer-2 TVL thresholds. The list updates weekly; biggest volume sits on BTC and ETH price forecasts.