Highest temperature in Tokyo on August 11?

Platform comparison

Market context

Tokyo's maximum temperature on 11 August 2026 will be recorded at Haneda Airport Station and resolved against the Daily Observations table on Weather Underground, with settlement occurring at midday UTC. The current crowd-implied probability of 0% YES reflects either extreme confidence in a specific temperature range or minimal trading activity on this contract. Cross-platform comparison reveals no meaningful divergence: sportsbooks do not typically quote weather outcomes, whilst prediction markets and analyst consensus on Japanese summer temperatures cluster around established seasonal patterns rather than outlier scenarios.

August in Tokyo historically produces daily highs between 32–36°C, with extreme readings above 37°C occurring in roughly one year per decade. The 2023 summer saw Haneda record 35.1°C on 11 August; the 2022 equivalent was 34.2°C. These precedents establish the baseline against which traders should calibrate their position. The Japan Meteorological Agency's seasonal outlook, typically released in late June, will provide the first formal guidance on whether 2026 summer conditions favour above-average or below-average heat.

Traders should monitor the Pacific High pressure system's positioning in late July and early August, as this drives the intensity of heat waves across the Kanto region. El Niño or La Niña conditions, confirmed by NOAA by mid-2026, influence seasonal temperature trajectories across East Asia. Haneda's urban heat island effect and its proximity to Tokyo Bay mean local readings often exceed rural stations; this institutional detail matters for resolution accuracy. The specification requiring Daily Observations data rather than the Day High & Low summary eliminates ambiguity but demands precise source verification at settlement.

Methodology

We track Highest temperature in Tokyo on August 11? 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

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 PolyGram. 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.

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 PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.