Highest temperature in Tokyo on August 10?

Platform comparison

Market context

Tokyo’s temperature on 10 August will be determined by the highest reading at Haneda Airport Station, with settlement tied to the Weather Underground Daily Observations table rather than the site’s day summary. The market is currently priced at **0% YES**, which is far below the live Polymarket-style crowd view in the search results, where the most likely band is centred on **31°C** and **30°C** rather than a higher or lower bin.[7]

Historical context points to a late-summer Tokyo peak that usually lands in the low 30s Celsius, with August averaging around **29°C** and typical highs near **31°C**.[8][13] Recent Japanese weather coverage also shows the broader heat regime has been extreme, with Japan posting record highs and Tokyo logging repeated 35°C+ days in the last year, so traders should not treat a low single-digit or mid-20s outcome as the base case in midsummer.[6][14] On that framing, a **0%** market price is unusual unless it reflects a data-source mismatch, thin liquidity, or a mistaken assumption about the settlement rule.

The main catalysts are the actual hourly observations at Haneda and any revision to the Wunderground record before the first datapoint for the next day is published, because that is what decides the contract. Weather Underground forecasts and Japan Meteorological Agency updates can move expectations during the day, but the decisive factor is the observed maximum in the settlement window, not the forecast high.[2][7] With Tokyo already under seasonally hot conditions and neighbouring forecast services pointing to around **90°F** highs, the live temperature path through the afternoon matters more than the morning state.[1][4]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Tokyo on August 10? 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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Best Prediction Markets. 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.

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Best Prediction Markets trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.