Highest temperature in Tokyo on August 14?

Platform comparison

Market context

The market is pricing the peak temperature at Tokyo Haneda Airport on 14 August 2026 at 0% probability for any given range, suggesting traders expect the settlement window to close before meaningful data emerges or that the resolution criteria present technical barriers. August in Tokyo typically sees daily highs between 32–35°C, with extreme heat events occasionally pushing toward 37–38°C. The 0% crowd probability reflects either extreme uncertainty about which temperature band will resolve, or scepticism about the market's ability to settle cleanly given its reliance on Weather Underground's Daily Observations table rather than the more commonly cited Day High & Low summary.

Historical August temperatures at Haneda show considerable year-to-year variance. The 2023 summer saw Tokyo record 37.5°C on multiple days during mid-August, whilst cooler years have peaked near 33°C. The specificity of using Haneda Airport's station data—rather than central Tokyo readings—introduces a geographic variable; airport microclimates can differ from urban centres by 1–2°C depending on wind patterns and surface conditions. Traders should note that the settlement window closes at 12:00 UTC on 14 August, which is 21:00 JST the same day, potentially creating ambiguity if the day's peak temperature occurs after that timestamp.

Monitoring Japan Meteorological Agency forecasts in early August will be essential, as seasonal patterns and any approaching weather systems could shift expectations significantly. The market's reliance on a specific data source and table format means traders should verify access to Weather Underground's Daily Observations table before committing capital, given the 0% pricing suggests limited confidence in clean resolution.

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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

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.

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 Who Will Win 2026 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.