Highest temperature in Shanghai on August 18?

Platform comparison

Market context

Shanghai's highest temperature on 18 August 2026 will be measured at Pudong International Airport Station and resolved against Weather Underground's Daily Observations table, with settlement occurring at midday UTC on that date. The 0% crowd probability reflects the inherent difficulty in forecasting a specific day's peak temperature nearly two years in advance, though this represents an extreme underestimation of the likelihood that *some* temperature range will occur.

August represents Shanghai's hottest month climatologically, with daily highs typically ranging between 32–35°C, though extremes occasionally exceed 37°C during heat waves. Historical data from the past decade shows that mid-August temperatures in Shanghai have rarely fallen below 30°C or exceeded 40°C on any single day. The current market pricing suggests traders are either treating this as a binary outcome rather than a range-selection exercise, or have misunderstood the resolution mechanics. Comparable weather markets on other platforms typically show meaningful probability mass distributed across multiple temperature bands for summer dates in subtropical regions.

Traders should monitor China Meteorological Administration seasonal forecasts released in the months preceding August 2026, as these often signal whether the summer will trend warmer or cooler than climatological norms. El Niño or La Niña conditions developing in 2025–2026 could influence regional temperature patterns. The specific resolution source dependency on Weather Underground's Daily Observations table—rather than official CMA data or airport summaries—introduces a minor technical risk; traders should verify the station's historical data availability and any potential reporting gaps before committing capital.

Methodology

This page reviews Highest temperature in Shanghai on August 18? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Best Prediction Markets, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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 Best Prediction Markets. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

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.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

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.