Highest temperature in Guangzhou on July 7?

Platform comparison

Market context

The underlying event is the highest temperature recorded at Guangzhou Baiyun International Airport on 7 July 2026, with the market currently pricing a 34°C peak as a 0% chance. Historical data frames this probability starkly: July in Guangzhou typically sees daily highs around 33°C (91°F), rarely dropping below 29°C (85°F) or exceeding 36°C (96°F), while the month’s hottest days can reach 39°C (102°F) [2][8]. A similar market on 3 July 2026 priced a 34°C peak at 27.5%, which ultimately settled as the correct outcome, suggesting traders should treat the current 0% probability as an outlier rather than a reliable forecast [1].

Traders must monitor real-time weather feeds from Wunderground for the station’s daily high, as cloud cover, thunderstorms, or heatwave intensification could shift temperatures unexpectedly [6]. Recent reports confirm China is experiencing record heatwaves, with Guangzhou’s July average temperature hitting 23.3°C—the highest since 1961—indicating broader climatic pressure that could elevate peaks beyond typical ranges [3][5]. While crypto markets tie into USDC settlement and BTC/ETH macro flows, the contract’s resolution hinges solely on physical weather data, making funding rates or whale flows irrelevant to the outcome [6].

Sources: 1 · 2 · 3 · 4 · 5

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

Why USDC and not ETH or USDT?

USDC is the Polygon standard — audited reserves (Circle, monthly attestation), deepest order book, low gas costs. ETH volatility would distort probability quotes; USDT has thinner Polygon liquidity than USDC.

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.

Can I use Bitcoin directly?

No, Polymarket operates exclusively in USDC on Polygon. You can bridge BTC to USDC via an exchange or bridge service and deposit on Polygon — typically 10-30 minutes processing time.

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.

Are crypto prediction markets taxable in the US?

In the US, prediction market gains are typically treated as ordinary income or short-term capital gains depending on holding period. Consult a tax professional for your specific situation — we cannot provide tax advice.