Highest temperature in Tokyo on August 14?

Platform comparison

Market context

Tokyo's highest temperature on 14 August 2026 will be measured at Haneda Airport Station and recorded in Weather Underground's Daily Observations table, with settlement occurring at midday UTC. The current market pricing reflects 0% probability across all temperature bands, suggesting either minimal trading activity or genuine uncertainty about which range will resolve. USDC conditional tokens on Polygon are trading at prices that imply traders see this as genuinely open, with no consensus forming around any particular temperature bracket despite August being Tokyo's hottest month.

Historical August temperatures at Haneda provide the essential baseline. Over the past decade, daily highs in mid-August have ranged from 32°C to 37°C, with 2023 recording 36.9°C on 14 August itself. The 2010 heatwave pushed readings to 39.1°C, establishing that extreme outliers remain within the realm of possibility. These precedents matter because they anchor what "typical" versus "exceptional" means—a 35°C day is routine, whilst anything above 37°C represents a notably warm outlier for that specific date.

Traders should monitor Japan Meteorological Agency forecasts released in early August, which typically provide 10-day outlooks by early-to-mid month. El Niño or La Niña conditions heading into northern hemisphere summer will influence broader temperature patterns, whilst any typhoon activity in early August could suppress temperatures through cloud cover and precipitation. The settlement mechanism's reliance on Haneda's specific station data rather than Tokyo's broader urban average means localised airport weather patterns—including tarmac heat effects—become material to the outcome.

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

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.

UK Frequently Asked Questions

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.

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%.