Highest temperature in Tokyo on August 10?

Platform comparison

Market context

Tokyo’s highest temperature is set to settle into the **30–32°C** band, with the crowd currently pricing a **0% YES** position under the market’s exact bracket rules. That stands in clear contrast to Polymarket’s own live book on the same event, where **31°C** is the front-runner at **54%** and **30°C** is next at **38%**, with **32°C** still a meaningful tail at **11%**.[5] The gap suggests either an unusually bearish read elsewhere on the contract, or a market that is underweighting how quickly Tokyo can still spike later in the day if sunshine and weak mixing persist.

Comparable August data point to a city whose daily highs often land in the low 30s Celsius, with average August highs around **31°C** and occasional hotter outcomes above that level.[8][12] Recent Japan-wide heat has also been extreme, with the Japan Meteorological Agency and major outlets reporting record-breaking national temperatures in 2025, including **41.8°C** in Isesaki and a run of severe heat across the archipelago.[9][14] That backdrop matters for a Tokyo daytime high market because it raises the ceiling for a surprise **32°C+** print even when the modal outcome remains around **30–31°C**.[4][5]

The key catalysts are straightforward: intraday cloud cover, sea-breeze effects, and any late-morning shower activity near Haneda can cap the high, while a clearer, sunnier run would push the observation closer to the upper end of the quoted range.[3][4] Traders should also watch the resolution mechanics closely, because this contract settles off the **Weather Underground Daily Observations** table rather than the summary high/low, so the final print depends on the exact station observation and not a broader city forecast.[5] Any discrepancy between different weather platforms will matter less than the airport station’s recorded maximum in the settlement window.

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 PolyGram, 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

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.

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.

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.