Highest temperature in Beijing on August 21?

Platform comparison

Market context

Beijing's maximum temperature on 21 August 2026 will be recorded at the Capital International Airport meteorological station and reported through Weather Underground's Daily Observations table. The settlement mechanism specifies this granular data source rather than the rounded summary figures, meaning traders require programmatic access to the raw observation logs to verify outcomes. This distinction matters: automated resolution checkers and conditional order systems must query the correct endpoint to avoid false triggers.

Historical August temperatures in Beijing cluster between 26–32°C, with extreme highs occasionally reaching 34–36°C during heat waves. The 0% crowd probability suggests either market participants expect below-range outcomes or the market has attracted minimal liquidity. Comparable August days from 2015–2024 show that temperatures above 35°C occur roughly once per decade in this window, whilst readings below 25°C are exceptionally rare. A trader building a systematic approach would cross-reference the China Meteorological Administration's seasonal forecasts against Weather Underground's historical variance to calibrate range expectations.

Catalysts for August 2026 conditions remain distant, though the Asian summer monsoon pattern and any developing El Niño or La Niña conditions will influence jet stream positioning by late summer. Near-term monitoring should focus on June–July 2026 temperature trends and any official forecasts issued by the CMA in early August. For programmatic traders, setting up conditional orders requires confirming that Weather Underground maintains continuous station coverage at Beijing Capital Airport and establishing fallback resolution protocols if data gaps occur during the settlement window.

Methodology

This page reviews Highest temperature in Beijing on August 21? 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 Polymarket Review UK, which mirrors the Polymarket order book at 0% fees.

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.

UK Frequently Asked Questions

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 Polymarket Review UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.