Highest temperature in Tokyo on July 17?

Platform comparison

Market context

Tokyo faces its peak summer heat on 17 July 2026, with the highest temperature recorded at Tokyo Haneda Airport Station set to determine the outcome of a weather prediction market. The contract, priced on Polymarket using USDC on the Polygon network, currently shows the 32°C range as the frontrunner with a 100% implied probability, while the “YES” outcome for any alternative range sits at 0% [1]. This pricing reflects the market’s confidence that temperatures will breach the lower thresholds, aligning with typical mid-July conditions in the region.

Historically, Tokyo’s July highs frequently reach 30–34°C, with Haneda Airport often recording similar peaks due to its coastal exposure and urban heat influence. Comparable cases from recent years show that temperatures below 25°C in mid-July are rare, supporting the market’s heavy weighting toward the 32°C outcome [1]. The 0% probability for lower ranges suggests traders view cooler outcomes as statistically negligible based on seasonal norms.

Traders should monitor real-time weather updates from Wunderground, the designated resolution source, as hourly temperature readings will directly impact settlement. Any sudden shifts in cloud cover, rainfall, or wind patterns could alter the day’s peak, though such events are uncommon in July. The market’s conditional token structure ensures automatic settlement once the official data is published, with no manual intervention required [1].

Sources: 1

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

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 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.