Highest temperature in Tokyo on August 1?

Platform comparison

Market context

Polymarket prices this Tokyo heat contract at **0% YES**, even though the event is simply the day’s highest temperature at Tokyo Haneda Airport Station and the market settles from the Wunderground daily history page in **USDC on Polygon** via conditional tokens. With the cut-off at 12:00 UTC, traders are effectively looking at the full local daytime heating cycle in Tokyo rather than an abstract monthly climate bet.

The historical frame is straightforward: August is Tokyo’s hottest month, with typical highs around **31°C** and occasional peaks in the high 30s, while recent regional summers have repeatedly produced exceptional heat. Tokyo’s August record high is listed at **39°C** on weather summary sites, and Japan has just seen record-breaking national heat in 2025, including **41.8°C** in Isesaki and multiple days above 35°C in Tokyo, which shows how quickly a seemingly routine summer day can move into extreme territory.[1][3][10][18]

For traders, the key catalysts are the morning-to-afternoon forecast updates, the strength of sunshine and humidity, and whether a late-day sea breeze, cloud cover, or rain bands cap the maximum before the settlement window closes. Haneda’s official reading is what matters, so city-centre weather can diverge from the station’s value; that makes the exact airport forecast more relevant than Tokyo-wide averages. Recent August guidance points to highs around **82°F to 90°F** and muggy conditions, which is consistent with a non-zero chance of a mid-to-high 30s print if heat builds efficiently.[6][14][19]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Tokyo on August 1? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

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 PolyGram. 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 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.