Highest temperature in Tokyo on July 13?

Platform comparison

Market context

Tokyo is set to experience mid-July heat today, with the Tokyo Haneda Airport Station expected to record its daily high temperature within the typical summer range. The prediction market for the highest temperature on 13 July 2026 currently prices the YES outcome at 0%, implying the crowd believes the temperature will fall outside the specific range defined for that contract. This near-zero probability aligns with historical patterns where Haneda’s July highs rarely exceed 36°C, though extreme outliers have occurred elsewhere in Japan.

Historically, Haneda’s July maximums hover between 28°C and 34°C, with the 76°–91°F (24°–33°C) forecast for July 2026 reinforcing the likelihood of a moderate peak [1][2]. While Japan recorded a national record of 41.2°C in Tamba City in late July 2025, that extreme was not observed in Tokyo’s urban core or at Haneda [3][5]. The 0% market price suggests traders are confident the day will not breach the upper threshold of the contract’s range, consistent with Haneda’s typical maritime moderation.

Traders should monitor real-time updates from Wunderground, the official resolution source, and watch for thundery showers forecast for Monday 13 July, which could suppress peak temperatures [4]. The Met Office also predicts a maximum of 31°C for Haneda today, further supporting the crowd’s bearish stance [2]. Any sudden shift in atmospheric pressure or unforecasted heat dome activity would be the primary catalyst to reassess the 0% probability, though current data offers no such indication.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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 Kalshi UK. 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.

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.