Highest temperature in Shenzhen on August 1?

Platform comparison

Market context

Shenzhen’s highest temperature on 1 August is usually a straightforward hot-season read, but this contract settles on the **peak** reading at Shenzhen Bao'an International Airport Station, not the daily average. That distinction matters because the market is sensitive to short-lived spikes, sea-breeze relief, and any afternoon convective heat burst; the crowd-implied **0% YES** looks far below normal August climatology, where several sources cluster around daily highs of roughly **31–32°C** and occasional peaks in the mid-30s°C for the city generally.[2][4][5][10]

Historical framing points to a market that is being priced as if an extreme outcome is very unlikely, even though Shenzhen in August is routinely hot and humid. WeatherSpark puts typical August daily highs around **89°F** with rare excursions above **93°F**, while other climate summaries show average highs near **90°F** and humidity around **79%**.[5][10] Comparable August history for Shenzhen shows plenty of days finishing around **88–90°F** and some hotter spells near **97°F**, which means the implied zero may reflect the contract’s exact source and airport station rather than a belief that the city will be cool.[1][4][9]

For traders, the main catalysts are the day’s synoptic setup and any late-shifting tropical or monsoonal influence affecting southern Guangdong, rather than scheduled domestic announcements. The key dependency is the official Wunderground history page for Shenzhen Bao'an International Airport Station, because the market resolves to that station’s highest temperature for the full day; if local cloud cover, rain bands, or typhoon-adjacent flow suppress afternoon heating, the outcome can stay in the lower range even when broader Shenzhen readings are warm.[17] Because settlement closes at **12:00 UTC**, the decisive temperature is still developing during the morning UTC window, so live regional weather updates and airport-station observations carry more weight than overnight forecasts alone.[17]

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 Kalshi vs Polymarket. 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi vs Polymarket trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.