Highest temperature in Shanghai on July 18?

Platform comparison

Market context

Shanghai's summer temperatures in mid-July typically peak between 32°C and 36°C, with occasional excursions above 37°C during heat waves. The settlement mechanism relies on Wunderground's historical weather archive for Shanghai Pudong International Airport Station, which records hourly observations and derives daily highs. A trader automating this market would need to parse Wunderground's data structure and cross-reference against the resolution window closing at 12:00 UTC on 18 July 2026—notably six hours after local midnight, creating a timing dependency for traders in Asian time zones.

Historical July records for Shanghai show the airport station has recorded temperatures exceeding 38°C in roughly one year per decade, with 2013 and 2017 producing particularly severe heat events. The 0% crowd probability suggests market participants are pricing in a specific temperature threshold as unlikely, though without visibility into the exact range boundaries, traders should verify whether the market is calibrated against historical percentiles or absolute thresholds. Programmatic traders would benefit from establishing a baseline forecast using seasonal climate models and comparing against the resolution source's historical archive directly rather than relying on third-party weather APIs, which may apply different station-selection or aggregation logic.

China's meteorological bureau publishes heat wave alerts and temperature forecasts through official channels; monitoring these announcements in early July would provide early signals for conditional orders. The absence of recent extreme weather patterns in Shanghai's first half of 2026 data would be a key input for updating priors closer to settlement.

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

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

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 Polymarket Review 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 Polymarket Review UK 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.