Highest temperature in Tokyo on August 11?

Platform comparison

Market context

Tokyo's maximum temperature on 11 August 2026 will be measured at Haneda Airport Station and recorded in Weather Underground's Daily Observations table, with settlement in USDC against the specified temperature band. The 0% crowd probability suggests traders are either confident the threshold will not be breached or have not yet priced in August's typical heat patterns for the region.

Historical August temperatures at Haneda show consistent peaks between 32–35°C, with occasional excursions to 36–37°C during heat waves. The Japan Meteorological Agency's records from the past decade indicate that extreme heat events in Tokyo cluster around mid-August, driven by the Bonin high-pressure system and tropical air masses. August 2023 saw Haneda record 35.1°C on the 11th; 2022 peaked at 34.8°C on that date. These precedents frame the baseline expectation: temperatures in the low-to-mid 30s are modal, whilst readings above 35°C occur in roughly one year in three during this period.

Traders should monitor the Japan Meteorological Agency's seasonal forecasts, updated monthly, which typically issue heat-wave alerts 7–10 days ahead of anomalous conditions. Sea surface temperatures in the Western Pacific and the strength of the Bonin high in early August will be material signals. Weather Underground's data feed has historically shown minor discrepancies between its Daily Observations and Day High & Low summaries; the contract's explicit reliance on the former reduces settlement ambiguity but requires traders to verify the source directly rather than relying on secondary summaries. USDC settlement occurs post-window closure, with no funding-rate mechanics tied to this market.

Methodology

Methodologically this overview focuses on on-chain pricing: Polymarket's live mid comes from the Polygon conditional-token order book and settles automatically in USDC. The other three venues — Kalshi, Betfair, Manifold — sit alongside as off-chain reference points so you can see how the contract translates across regulatory and settlement regimes.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

UK Frequently Asked Questions

What does a transaction cost on Polygon?

Polygon gas is typically under $0.01 per transaction. A full trade cycle (Approve + Order + Fill) totals around $0.03 — compared to $5-50 on Ethereum mainnet.

Can I use Bitcoin directly?

No, Polymarket operates exclusively in USDC on Polygon. You can bridge BTC to USDC via an exchange or bridge service and deposit on Polygon — typically 10-30 minutes processing time.

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%.