Highest temperature in Tokyo on August 15?

Platform comparison

Market context

Tokyo's weather on 15 August 2026 will be shaped by the tail end of the Japanese summer monsoon season, when the city typically experiences peak heat and humidity. August is consistently Tokyo's hottest month, with daily highs averaging 32–33°C at Haneda Airport, though extremes regularly exceed 35°C. The 0% crowd probability suggests traders are either uncertain about the specific temperature threshold being tested or expect conditions to fall below the lowest range option available.

Historical August data from Haneda shows considerable year-to-year variability. The station recorded 37.0°C on 16 August 2023 and 36.4°C on 15 August 2013, establishing that mid-August peaks above 36°C occur roughly once per decade. Conversely, cooler August days with highs near 30°C are rare but possible during years when Pacific high-pressure systems weaken or typhoon activity disrupts typical patterns. The settlement specification requiring Daily Observations data rather than summary figures matters operationally, as intraday readings can differ slightly from rounded daily highs.

Traders should monitor tropical cyclone forecasts issued by the Japan Meteorological Agency in early August, as typhoons or their remnants can suppress temperatures significantly. Additionally, any unusual atmospheric blocking patterns developing in late July will signal whether typical August heat persists or weakens. The resolution window closes at 12:00 UTC on 15 August, meaning the market settles on actual recorded data from that specific date at Haneda, with no adjustment for subsequent corrections.

Methodology

We track Highest temperature in Tokyo on August 15? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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

Is this market available outside the US?

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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.

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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%.