Highest temperature in Shanghai on July 28?

Platform comparison

Market context

Shanghai will record its highest daily temperature on 28 July 2026, measured at Pudong International Airport Station. The settlement hinges on Wunderground's historical weather database, which logs hourly readings throughout the day. The 0% crowd probability suggests either extreme confidence in a specific temperature band or minimal trading volume on this particular outcome range—a common pattern for granular weather markets where liquidity clusters around round-number thresholds rather than distributing evenly across all bins.

Shanghai's July climate is remarkably consistent. Historical data from the past decade shows peak temperatures on late-July days clustering between 32–36°C, with occasional spikes to 37–38°C during heat waves. The 2013 heat event reached 40.8°C, but such extremes occur roughly once per decade. Comparing across platforms, Kalshi's binary structure would frame this differently than Polymarket's categorical bins or Betfair's decimal odds approach; each platform's fee structure (Kalshi's 2% settlement fee versus Betfair's commission model) alters the effective payout at different probability levels, particularly relevant when implied probabilities sit at extremes like 0%.

Traders should monitor mid-July weather pattern forecasts from China's Meteorological Administration, typically released fortnightly. El Niño or La Niña conditions influence East Asian summer temperatures; current neutral conditions suggest baseline expectations. The settlement window closes at midday UTC on 28 July, creating a hard deadline for final readings—traders in Western time zones face a compressed window to react to morning data releases from Shanghai.

Methodology

This page compares Highest temperature in Shanghai on July 28? 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 Kalshi Alternative UK, 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

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

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.

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. Kalshi Alternative UK 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.