Highest temperature in Tokyo on August 15?

Platform comparison

Market context

The market seeks the peak temperature recorded at Tokyo Haneda Airport on 15 August 2026, with settlement based on Weather Underground's Daily Observations table rather than summary figures. The 0% implied probability suggests traders expect the specified temperature range to fall outside historical norms for mid-August in Tokyo, or that consensus has coalesced around a particular band entirely.

Tokyo's August temperatures are remarkably consistent. Historical data from 1990 onwards shows mid-August highs clustering between 32–35°C, with extremes rarely breaching 37°C even during heatwave years. The 2010 heatwave pushed Haneda to 36.9°C on 16 August; the 2013 peak reached 35.1°C on the 15th itself. These precedents frame the likely outcome space. A 0% probability on any single range suggests either that range sits at an implausible extreme—well above 38°C or below 30°C—or that the market has already settled on a consensus band with near-certainty, leaving no perceived value in alternatives.

Traders monitoring this market should track Japan Meteorological Agency forecasts as August 2026 approaches, particularly any alerts for unusual heat systems or typhoon activity that could suppress temperatures. La Niña or El Niño conditions developing through 2025–2026 could shift seasonal patterns, though historical volatility around the 15th remains modest. Haneda's urban heat island effect and airport infrastructure create a stable microclimate, making dramatic departures from the 32–35°C range unlikely unless a major weather system intervenes directly.

Methodology

We track Highest temperature in Tokyo on August 15? 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

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

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.

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.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.