Highest temperature in Tokyo on June 30?

Platform comparison

Market context

The real-world event at the heart of this market is the highest temperature recorded at Tokyo Haneda Airport on 30 June 2026, measured in degrees Celsius. In prediction markets, a YES share pays out if the temperature falls within the specified range, while a NO share pays out if it does not. Here, the crowd-implied probability of YES is 0%, meaning traders are virtually certain the temperature will not match the range in question. This extreme confidence suggests the market expects a temperature far outside the target band, likely due to prevailing seasonal patterns.

Historically, late June in Tokyo is already warm, with average highs around 28°C, but record-breaking heat is rare at Haneda. Recent data shows Tokyo hit 36.4°C in June 2025 during a record-breaking heatwave, yet Haneda typically remains slightly cooler than central Tokyo [8]. The 41.2°C record set in Tamba in July 2025 is not representative of Haneda’s climate [2]. Given these precedents, a 0% YES probability aligns with expectations that the temperature will stay within the typical 26–30°C range, not the extreme range implied by the market.

Traders should monitor daily forecasts from AccuWeather and JAL for any sudden shifts in humidity or cloud cover, which can suppress peak temperatures [4][7]. A key dependency is the release of official Wunderground data after 12:00 UTC on 30 June, which will confirm the final reading [1]. While no immediate announcements are expected, the ongoing climate trend of hotter summers in Japan may influence future markets, though it does not currently alter this one’s outcome [2].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Tokyo on June 30? 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

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.

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.

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.