Highest temperature in Chengdu on August 11?

Platform comparison

Market context

Chengdu will experience peak summer heat on 11 August 2026, with the highest temperature recorded at Shuangliu International Airport determining the market outcome. The resolution mechanism specifies the Daily Observations table from Weather Underground as the authoritative source, bypassing the Day High & Low summary section—a distinction that matters when automated feeds pull data from multiple endpoints. For programmatic traders, this means validating the exact table structure before settlement and accounting for potential lag between real-time displays and the historical record that resolves the market.

Chengdu's August temperatures have historically clustered between 32–36°C, with extremes reaching 39–40°C during heat waves. The 0% crowd probability suggests either market participants expect a notably cool August or the market has insufficient liquidity and attention. Comparable August settlements at similar latitude and elevation (Chengdu sits at 505 metres) show that 35–37°C ranges capture the majority of outcomes, whilst readings above 38°C occur roughly once per decade. Traders should cross-reference historical Weather Underground records for Shuangliu station to calibrate their own temperature bands.

The key variable is whether a high-pressure system dominates central China during early August 2026. Seasonal forecasts from the China Meteorological Administration typically publish outlooks 1–2 months ahead; traders should monitor these releases for signals of above or below-normal temperatures. Additionally, any El Niño or La Niña conditions active in mid-2026 will influence regional atmospheric patterns. Setting up conditional orders tied to CMA forecast updates or temperature thresholds from nearby stations (Chongqing, Wuhan) provides a practical hedge whilst awaiting the settlement window.

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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

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.

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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi Fees trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.