Highest temperature in Tokyo on August 12?

Platform comparison

Market context

Tokyo's highest temperature on 12 August 2026 will be recorded at Haneda Airport Station and measured against historical August patterns in the Kanto region. The current 0% implied probability reflects either extreme confidence in a specific temperature range or minimal trading activity on this particular date-and-range combination. August in Tokyo typically sees daily highs between 32–35°C, with occasional peaks above 36°C during heat waves; the settlement mechanism specifies the Weather Underground Daily Observations table as the authoritative source, which occasionally diverges from summary displays and matters for edge cases near range boundaries.

Historical August temperatures at Haneda show considerable year-to-year variation. The 2010 heat wave produced 39.5°C; conversely, cooler Augusts have peaked near 31°C. Traders comparing this market across platforms will encounter different odds formats: Polymarket displays decimal odds and charges 2% on both sides, whilst Kalshi uses American odds with tiered fees based on contract value, and Betfair's decimal odds structure attracts European liquidity. Smarkets similarly uses decimals but with lower taker fees (2% vs Polymarket's standard rate). Geographic KYC restrictions vary—Kalshi requires US residency for most users, whilst Polymarket and Smarkets serve broader international audiences, affecting where liquidity concentrates.

Traders should monitor Japan Meteorological Agency forecasts released in early August and track any El Niño or Pacific pressure system developments that influence late-summer heat patterns. The settlement window closes at midday UTC on 12 August, creating a narrow window for final adjustments once actual morning temperatures become visible.

Methodology

We read Highest temperature in Tokyo on August 12? from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live mid is the canonical probability; the side-by-side columns benchmark fees, KYC, settlement currency and deposit rails so you can choose the venue that fits your jurisdiction and trade size.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). On-chain settlement clears in minutes — the fastest payout path of the four.

FAQ

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Polymarket Alternative has a different geo footprint and routes to Polymarket's order book at 0% fees.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Polymarket Alternative offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.