Highest temperature in Shanghai on July 27?

Platform comparison

Market context

Shanghai is starting the day warm and unsettled, with forecast highs around 31–38°C and a risk of showers or thunderstorms later, which leaves the midday peak uncertain but still comfortably above average for late July.[2][6][7] The market is resolved from the highest temperature recorded at Shanghai Pudong International Airport Station on the day, so the key question is whether the airport gets a brief pre-rain spike or whether cloud and rain cap the top end before the afternoon.[2][14]

The 0% implied YES probability is best read against Shanghai’s July climate: hot, humid, and frequently rainy, with typical daytime highs around 30–32°C and occasional extremes near 40°C in very hot years.[1][3][8] That means the distribution is broad enough for a high temperature well above the monthly average, but the presence of forecast precipitation makes the upper tail more dependent on timing than on seasonal warmth alone.[2][6] Comparable July patterns in Shanghai often produce a short-lived morning or late-morning high before convection builds, so the relevant comparator is not just the monthly mean, but whether today behaves like a clear, heating-led day or a cloud-dominated one.[2][8]

For traders, the immediate catalysts are the live hourly forecast changes, especially any shift in rain timing, cloud cover, or wind direction that could either allow a higher pre-rain maximum or suppress heating altogether.[2][10][11] The official Chinese city forecast cited in local reporting points to 28–38°C with local afternoon showers or thunderstorms, while regional weather bulletins also show Shanghai in rain for the day, underscoring that the main dependency is still the exact arrival of convection.[6][7] Because the settlement source is airport station data on Wunderground, the most useful watch item is the station’s recorded maximum through the day rather than citywide averages or feels-like figures.[14]

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

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.

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 Prediction Today. 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 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 Prediction Today trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.