Highest temperature in Tokyo on July 31?

Platform comparison

Market context

Tokyo’s highest temperature will be set by the day’s warmest reading at Haneda Airport, so the practical question is whether 31 July produces a **0–5°C band** or something materially hotter. At 09:00 UTC, Tokyo is already into the afternoon, which matters for automated setups: a bot watching the Wunderground daily page can simply poll the station’s current daily high and compare it with the remaining forecast window before the local close. Tokyo’s July climatology is hot and humid, with typical daytime maxima around the high 20s Celsius, but the station-level settlement source is what counts, not citywide averages.[1][12]

The current **0% YES** crowd price looks uninformative rather than a true forecast, because recent July heat in Japan has repeatedly exceeded normal expectations. Tokyo’s own historic July 2025 reading reached 93°F, about 33.9°C, on 31 July in Timeanddate’s archive, while Japan as a whole has recently logged extreme heat above 40°C in western prefectures.[2][4][5] For traders modelling this programmatically, the relevant comparison is not national records but the Haneda station’s own intraday trajectory, plus how late-day convection or sea-breeze effects can cap the maximum. A rules-based approach would map the live Wunderground high to the market’s settlement bands and update exposure only when the observed high crosses a new threshold.

The main catalysts are therefore local weather dynamics and the final hours of the Tokyo session: cloud cover, rainfall, wind shift, and any heat advisory that could prolong the climb before the daily maximum is locked in. Japan’s weather service has recently highlighted dangerous heat conditions elsewhere in the country, showing that summer surges can arrive quickly even when broader averages look ordinary.[4][5] Programmatically, the cleanest workflow is to monitor the Wunderground history page directly, apply Celsius conversion, and trigger conditional orders only when the recorded high moves into the target range, since the market resolves from that source rather than from forecasts alone.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Polymarket Bot UK, which mirrors the Polymarket order book directly.

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'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.

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.