Highest temperature in Guangzhou on July 1?

Platform comparison

Market context

The highest temperature recorded at Guangzhou Baiyun International Airport on 1 July 2026 is the real-world event determining this contract’s outcome. Today, Polymarket prices the YES side for the 39°C+ range at 0%, implying the crowd sees virtually no chance of such extreme heat. This stark valuation contrasts sharply with historical precedent: on 1 July 2004, Guangzhou hit exactly 39.1°C, the city’s all-time record, as confirmed by extreme weather archives[3]. July is consistently Guangzhou’s hottest month, with average highs near 33°C (91°F) and peaks occasionally reaching 36°C (96.8°F)[5][8]. The 2024 July was China’s hottest month since 1961, setting a worrying baseline for future extremes[2][6].

Traders should monitor China’s National Meteorological Centre’s mid-June heatwave forecasts and any official announcements on urban cooling measures ahead of the settlement window. Recent Reuters reporting confirms that rising baseline temperatures are making record-breaking heat more plausible in coming years[6]. Key dependencies include the timing of the summer monsoon, which can suppress temperatures through rainfall, and the strength of the subtropical ridge, which drives prolonged high-pressure heat events. Wunderground’s daily data for ZGGG will be the definitive resolution source, so traders must watch for real-time anomalies in the 24-hour period ending 2026-07-01T12:00:00Z. The conditional tokens on Polygon, settled in USDC, will reflect these on-chain price movements as new weather data emerges.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Guangzhou on July 1? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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 PolyGram. 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'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 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.