Highest temperature in Guangzhou on July 31?

Platform comparison

Market context

Polymarket has this contract priced at **0% YES** in USDC terms on Polygon, which means the market is treating a July heat extreme at Guangzhou Baiyun International Airport as effectively unpriced rather than merely unlikely. Because settlement depends on the *highest* temperature recorded there on 31 July 2026, a trader is really buying exposure to the day’s peak reading on the Wunderground history page, not to a forecast average or the airport’s current conditions.

For context, late-July Guangzhou is normally a hot, humid, and storm-prone setup rather than a stable clear-sky one. July averages are around 30–33°C for daytime highs, with some guides putting typical July highs near 33°C and occasional maxima up to 36–37°C; recent forecast products also show a 31 July high in the low-to-mid 30s Celsius with thunderstorm risk. That makes the upper bands meaningful for this market: if the airport logs a peak above the threshold range, the conditional token settles accordingly, but a single cooler or rain-interrupted afternoon can keep the final print lower than the headline forecast.

The main catalysts are the day’s convection timing, rain bands, and whether thunderstorms build in the afternoon or hold off until after the maximum is set. Traders should watch the airport observation stream, short-range forecasts, and any rapid changes in humidity, cloud cover, or storm probability, because Guangzhou’s July heat often peaks before the strongest showers arrive. On Polymarket, that means the best read comes from comparing live updates against the settlement source rather than relying only on city-wide forecasts, since the contract resolves from the Baiyun Airport station’s recorded high, denominated in Celsius and ultimately cleared through the market’s on-chain conditional token mechanism.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Guangzhou on July 31? 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

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 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.