Highest temperature in Shenzhen on July 8?

Platform comparison

Market context

On 8 July 2026, the Shenzhen Bao'an International Airport Station will record its peak temperature for the day, a real-world event that determines the outcome of this prediction market. The crowd-implied probability for the 31°C bracket sits at 0% YES, suggesting the consensus heavily favours lower ranges, yet climatology tells a different story. July is Shenzhen’s hottest month, with an average high of 89°F (31.7°C), making any bracket below 31°C a below-normal outcome in a ten-way field[4][5]. Historical data from recent Polymarket events shows traders clustering tightly around 30–31°C for early July maximums, with 31°C commanding significant probability mass just days prior[1]. This divergence between the 0% market price and the climatological average presents a clear value spot for contrarian traders betting the temperature will hit or exceed 31°C.

Traders must monitor the immediate weather forecast and any sudden shifts in cloud cover or rain, which are the primary catalysts for temperature suppression. AccuWeather forecasts mostly cloudy conditions with periods of rain for 8 July, potentially capping the high near 88°F (31.1°C) or lower, while a morning thunderstorm on 9 July could indicate lingering instability[6]. The resolution source, Wunderground, will publish the definitive maximum temperature once the day concludes, but real-time dependencies like the Intertropical Convergence Zone’s position could alter the outcome. Given the forecast of 88°F with rain, the underdog 31°C bracket remains a high-risk, high-value proposition if the clouds clear unexpectedly, whereas the consensus on lower temperatures aligns with the current wet forecast[6][8].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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

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 Who Will Win. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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.