Highest temperature in Tokyo on July 4?

Platform comparison

Market context

The real-world event in question is the peak air temperature recorded at Tokyo Haneda Airport on 4 July 2026, measured in degrees Celsius. This single-day snapshot determines the market resolution, with settlement depending on Wunderground’s official daily high for the RJTT station. The current crowd-implied probability of 0% for the “YES” outcome suggests the market believes the temperature will not fall within a specific, likely low, threshold, though the frontrunner outcome is 27°C at 57% probability[1].

Historical data frames how to interpret this probability: Tokyo’s hot season runs from late June to mid-September, with average daily highs exceeding 79°F (26.1°C) and July’s mean temperature at 28.7°C (83.7°F)[6][8]. Recent records show Japan’s July average hit a record high for the third consecutive year, reinforcing that temperatures rarely dip below 26°C in early July[8]. The 2026 forecast for Haneda indicates daily highs between 76°F and 91°F (24.4°C–32.8°C), making sub-26°C outcomes statistically marginal[4].

Traders should monitor real-time weather feeds from the National Weather Service and Wunderground, as sudden shifts in cloud cover or wind patterns can alter the daily peak[3]. While no specific announcements are scheduled, the Met Office currently forecasts a maximum of 27°C for Haneda, aligning with the market’s frontrunner[9]. Programmatically, a power-user would deploy conditional orders triggered by Wunderground’s hourly updates, copying trades when the live high approaches 27°C to capture the 57% implied probability[1]. Dependencies include the settlement window ending at 12:00 UTC on 4 July 2026, requiring precise timing for position closure.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Tokyo on July 4? 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 Polymarket Review UK. 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'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.

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.