Highest temperature in Tokyo on August 11?

Platform comparison

Market context

Tokyo's weather on 11 August 2026 will depend heavily on whether the region experiences typical summer heat or an anomalous pattern. The 0% crowd probability suggests traders are pricing in either extreme confidence in a specific temperature range or uncertainty about which range the market is actually asking for. August in Tokyo typically sees daily highs between 32–35°C, with occasional peaks above 36°C during heat waves, though the exact settlement range thresholds remain critical to interpreting current odds.

Historical August temperatures at Tokyo Haneda Airport show that readings above 37°C occur roughly once every three to five years during the month, whilst temperatures below 30°C are exceptionally rare. The 2010 heat wave pushed readings to 39.5°C; more recently, August 2023 saw highs around 34–35°C. These precedents suggest that unless an unusual weather system develops, mid-range temperatures (33–36°C) remain most probable. The distinction between Weather Underground's Daily Observations table and the Day High & Low summary section matters operationally, as discrepancies occasionally arise from different measurement methodologies or timing windows.

Traders should monitor Japan Meteorological Agency forecasts released in late July and early August, which typically provide 10-day outlooks with increasing precision. Pacific typhoon activity in early August could shift conditions substantially; the agency's official advisories usually appear by 5 August. Additionally, any El Niño or La Niña developments affecting the broader Western Pacific will influence whether August 2026 tracks toward above-average or near-average temperatures for the season.

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

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

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

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%.