Highest temperature in Tokyo on August 10?

Platform comparison

Market context

Tokyo’s outcome depends on the **highest observed temperature at Haneda Airport** during the day, not the headline high shown in a summary box, so a programmatic approach should pull the Daily Observations table and watch for late revisions before the following day’s first datapoint appears. In practice, that means tracking the station-specific hourly record, mapping the top reading into the market’s Celsius bins, and not relying on generic city forecasts or app-level “day high” figures.[6]

A zero per cent crowd price is hard to square with the seasonal baseline. Tokyo’s August climatology is firmly hot: averages around 29°C, with typical highs near 31°C, and the current market is already clustered around 30–31°C in the live outcome ladder.[9][6] Japan has also just come through an exceptional run of heat, including record summer conditions nationwide and multiple days above 35°C, which matters because late-summer heat tends to persist rather than reset quickly.[4][13]

For traders running bots or conditional orders, the main catalysts are forecast updates, cloud cover, rain bands, and any shift in the Pacific subtropical high that would cap or amplify daytime warming. JMA observation data for Tokyo this morning already showed a hot start, with the broader day still capable of moving one bracket if sunshine holds and sea-breeze timing slips.[2][3] The practical workflow is simple: poll the source page, compare the latest maximum against the settlement bins, and expect the last usable read to come from the final Daily Observations entry before rollover.[6]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Tokyo on August 10? 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

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 Polymarket Review UK. 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%.