Highest temperature in Shanghai on August 12?

Platform comparison

Market context

Shanghai's peak temperature on 12 August 2026 will be measured at Pudong International Airport Station and recorded in Weather Underground's Daily Observations table, with resolution tied to that specific data source rather than the Day High & Low summary section. The 0% crowd probability reflects either extreme confidence in a narrow outcome or sparse liquidity on this niche weather contract.

August temperatures in Shanghai historically cluster between 32–36°C, with occasional peaks above 37°C during heat waves. The city experiences its hottest period in mid-to-late August, driven by subtropical high-pressure systems and urban heat island effects. Comparable forecasts on other platforms show similar settlement mechanics: Kalshi's weather contracts use NOAA data with decimal odds display, whilst Betfair's weather book typically quotes implied probabilities directly. The choice of Weather Underground as primary source here differs from US-focused platforms, which may explain why cross-platform comparison shows divergent liquidity and pricing—traders familiar with NOAA-based resolution may discount this contract's specificity.

The China Meteorological Administration issues 10-day forecasts updated daily; traders should monitor late July and early August bulletins for monsoon activity or heat dome formation across eastern China. Typhoon season activity in the Western Pacific can suppress temperatures, whilst stalled high-pressure systems drive peaks. Settlement precision depends entirely on Pudong station data availability; any gaps in Weather Underground's Daily Observations table could trigger resolution delays. KYC requirements vary across platforms—Polymarket's offshore structure contrasts sharply with Kalshi's US-regulated approach—affecting which traders can access this contract.

Methodology

This page compares Highest temperature in Shanghai on August 12? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Robinhood Prediction Markets, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Robinhood Prediction Markets has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.