Highest temperature in Shanghai on August 9?

Platform comparison

Market context

Shanghai’s high on 9 August will be set by what actually appears in Weather Underground’s Daily Observations for Shanghai Pudong International Airport, not by the headline day-high figure, so the market is effectively a read on whether the airport station logs a cooler, wetter outcome than typical August heat. The current crowd-implied probability of 0% YES is starkly lower than the broad forecast picture: AccuWeather’s 9 August outlook points to 85°F with heavy rain, and Weather.com.cn shows heavy rain with a 29°C high, both consistent with a cap on the day’s maximum rather than an extreme heat spike.[3][12]

Historically, Shanghai’s August weather is hot and humid, but it is also highly sensitive to rain bands and typhoon-adjacent systems. Long-run guides place typical August daytime highs around 31°C to 34.6°C, while recent forecast services for 9 August cluster in the upper 20s to low 30s Celsius, which would leave little room for an outlier above the highest bracket if showers arrive early and persist.[7][9][14] That makes the contract’s “range that contains the day’s maximum” more about whether the airport station reaches the low-30s or stalls below that band than about any precise degree reading.

Traders should watch the evolution of the local rainfall forecast, wind strength, and any typhoon or tropical-depression guidance over the next 24 hours, because the main driver here is not average heat but whether convective rain suppresses the afternoon maximum. AccuWeather is already flagging a 97% precipitation chance and gusts up to 41 mph for Sunday, while WorldWeatherOnline similarly indicates very heavy rain and strong winds on 9 August, which would support a lower terminal reading if verified at Pudong.[3][10] The key dependency is the station observation itself at the airport, since the market resolves from the Weather Underground daily observations table rather than a city-wide summary.[3]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Shanghai on August 9? 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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

UK Frequently Asked Questions

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 Best Prediction Markets UK. 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.

Do I need to KYC for this market?

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

What are the best prediction markets for UK traders in 2026?

For UKGC-regulated markets: Betfair Exchange (sports, politics) and Smarkets (sports, politics, lower commission than Betfair). For broader global event prediction: Polymarket (deepest liquidity, 0% fee, USDC settlement). For US-regulated option: Kalshi (USD, limited UK payment options). Most serious UK traders use a combination of Betfair for regulated sports and Polymarket for broader markets.