Highest temperature in Tokyo on August 19?

Platform comparison

Market context

The market seeks the highest temperature recorded at Tokyo Haneda Airport on 19 August 2026, with settlement based on Weather Underground's Daily Observations table rather than summary figures. The crowd currently assigns zero probability to any outcome, suggesting either extreme uncertainty or a technical issue with market initialisation. August in Tokyo typically sees peak summer heat, with historical daily highs ranging from 32–35°C, though extreme heat events occasionally push readings above 37°C.

Tokyo's August temperatures have shown considerable year-to-year variation. The city recorded 37.0°C on 16 August 2023 and 36.4°C on 20 August 2022, whilst cooler Augusts have produced highs around 31–32°C. The 0% crowd probability likely reflects the market's early stage rather than genuine consensus that no temperature will be recorded. Haneda Airport's coastal location moderates extremes slightly compared to central Tokyo, though the station remains subject to the same seasonal patterns. Historical data suggests the most probable range sits between 32–35°C, with outcomes above 36°C representing genuine outliers rather than base-case scenarios.

Traders should monitor Japan Meteorological Agency forecasts released in the weeks preceding 19 August, particularly any alerts for heat waves or unusual atmospheric patterns. El Niño or La Niña conditions influence Pacific-region summer temperatures, though 2026 forecasts remain preliminary. The resolution methodology—using Daily Observations rather than Day High & Low summaries—matters operationally; discrepancies between these sources have occasionally created settlement disputes on weather markets. Early market liquidity and pricing will likely remain thin until closer to the settlement date.

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Who Will Win, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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%.