Highest temperature in Tokyo on July 13?

Platform comparison

Market context

Tokyo’s peak summer heat is arriving as the city faces its hottest month, with July 2026 forecasts for Haneda indicating daily highs between 33°C and 35°C. The market currently prices a YES outcome at 0%, implying the crowd believes the temperature will fall outside the specified range, yet historical data shows Haneda regularly exceeds 35°C in mid-July, with the hottest month averaging above 26°C and peaks often reaching 35°C or higher [1][3]. Recent two-week data for the region recorded a high of 35.1°C (85.2°F) on 8 July 2026, suggesting the current 0% probability may be mispriced if the range includes 35°C or above [5].

Traders should monitor the Japan Meteorological Agency’s daily bulletins and Wunderground’s real-time updates for Haneda, as a sudden heatwave or urban heat island effect could push temperatures beyond consensus expectations [7][9]. The Met Office forecast for Monday, 13 July, predicts a maximum of 35°C with a 40% rain chance, which could suppress temperatures if precipitation occurs, but dry, high-pressure conditions would likely sustain or exceed this threshold [3]. With the settlement window closing at 12:00 UTC, the key catalyst is whether the day remains cloud-free; recent AccuWeather models show July 2026 highs ranging from 33°C to 35°C, making the 35°C+ range a potential value spot for contrarian traders [2].

Sources: 1 · 2 · 3 · 4 · 5

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.

FAQ

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 Who Will Win 2026. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Who Will Win 2026 trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.