Highest temperature in Tokyo on August 14?

Platform comparison

Market context

Tokyo's maximum temperature on 14 August 2026 will be measured at Haneda Airport Station and recorded in Weather Underground's Daily Observations table, with settlement tied to whichever temperature range bracket contains that single highest reading. The market currently prices this at 0% probability for YES outcomes, meaning traders are pricing in either extreme confidence in a specific temperature band or minimal liquidity across the conditional token pairs on Polygon.

August in Tokyo typically sees daily highs between 32–35°C, with occasional peaks above 36°C during heat waves. Historical data from the past decade shows that mid-August temperatures at Haneda have ranged from 29°C to 37.5°C, with the most frequent outcomes clustering around 33–34°C. The 0% crowd probability suggests traders have already committed capital to a particular temperature range, leaving other brackets effectively unpriced on the USDC-denominated contract. This pricing pattern often reflects early-market positioning rather than meteorological certainty.

The Japan Meteorological Agency issues its seasonal forecasts in early August, with updates to medium-range outlooks published daily. El Niño or La Niña conditions, tracked by NOAA, influence broader Pacific weather patterns that affect Tokyo's summer temperatures. Any significant tropical cyclone activity in the Western Pacific during early-to-mid August could alter atmospheric circulation and push temperatures either higher or lower than climatological norms. Traders should monitor JMA heat wave advisories and any official temperature anomaly forecasts released in the week before settlement, as these typically drive late repositioning in weather markets.

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

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

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.

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%.