Highest temperature in Shanghai on July 20?

Platform comparison

Market context

Shanghai faces a sweltering July 20, 2026, with forecasts predicting maximum temperatures near 38°C at Pudong International Airport, accompanied by scattered clouds and a high chance of local thunderstorms. The crowd-implied probability of 0% for the current market suggests traders believe the peak heat will fall outside the specific range offered, despite the region’s typical summer intensity.

Historical data for mid-July in Shanghai consistently shows highs between 34°C and 38°C, with 2024 and 2025 both recording peaks around 37°C during similar humid conditions. On platforms like Kalshi, such historical baselines often translate into decimal odds reflecting a 10–20% chance of exceeding 38°C, whereas Polymarket’s implied probability model here shows near-zero confidence, highlighting a divergence in how books interpret identical climate patterns.

Traders should monitor real-time updates from Wunderground and Meteoblue for sudden shifts in cloud cover or precipitation, which could suppress temperatures below the threshold. A recent Meteoblue forecast notes a 70% chance of precipitation and potential thunderstorms this afternoon, a key dependency that could invalidate higher-temperature bets. While Kalshi requires KYC and charges fees on wins, Polymarket’s permissionless structure and zero-KYC access allow faster positioning on such volatile weather catalysts, creating distinct liquidity dynamics for this event.

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Methodology

This page compares Highest temperature in Shanghai on July 20? 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.

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.

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.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Kalshi Alternative UK offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.