Highest temperature in Tokyo on July 27?

Platform comparison

Market context

Tokyo’s daytime high on 27 July will settle this market, using the highest temperature recorded at Tokyo Haneda Airport Station by the market’s Wunderground reference. The crowd is pricing **30°C** as the favourite at **39%**, with **31°C** next at **25%**, while the market-implied **0% YES** for the broader set of higher outcomes leaves the underdog side looking priced for a fairly tight, ordinary summer day rather than a heat spike.[1]

The historical frame is straightforward: late-July Tokyo is usually warm to very warm, but not every day breaks out into extreme heat. General July guides for Japan put temperatures around **17°C to 30°C**, and Tokyo’s July weather is typically humid, with tropical-storm disruption described as rare in a normal year.[2][3] That makes the consensus around the low-30s a sensible anchor, with value more likely in contrarian tails if a stronger-than-expected heat build develops. From a handicapper’s angle, the favourite is clearly the mid-range summer high; the underdog is anything that pushes the day’s peak materially above the low 30s.

The main catalysts are meteorological rather than calendar-driven: whether the Tokyo area sits under clear skies, how quickly the sea breeze mixes in at Haneda, and whether any afternoon convection or cloud cover suppresses the maximum. Traders should watch Japan Meteorological Agency forecasts and any updates on humidity, rainfall, or storm tracks, because small shifts in cloud cover can move the daily high by a degree or two. With the settlement window ending at **12:00 UTC**, the market is especially sensitive to the daytime heating profile in Tokyo rather than the overnight minimum.[1]

Sources: 1 · 2 · 3

Methodology

We track Highest temperature in Tokyo on July 27? 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

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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 Who Will Win. 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.

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.