Highest temperature in Tokyo on July 10?

Platform comparison

Market context

On 10 July 2026, the Tokyo Haneda Airport Station will record its daily peak temperature, resolving a prediction market that currently shows a 0% implied probability for any outcome exceeding 31°C on platforms like Kalshi, despite Polymarket assigning a 38% chance to exactly 31°C and 34% to 30°C. This divergence highlights how different books treat decimal odds versus implied probability: Polymarket’s crowd-driven model reflects a realistic spread for mid-July heat, while Kalshi’s institutional framework may suppress tail-risk pricing due to stricter fee structures and KYC requirements that limit retail participation.

Historical July highs at Haneda average 87°F (30.6°C), with recent forecasts for July 2026 projecting daily peaks between 79°F and 89°F (26.1°C–31.7°C), making 31°C a plausible upper bound rather than an outlier. The Met Office currently forecasts a maximum of 32°C for the region, and Japan’s Meteorological Agency recently recorded a national high of 41.2°C in Tamba, confirming that extreme heat events are increasingly common in the summer season. Traders should monitor the Japan Meteorological Agency’s daily bulletins and AccuWeather’s hourly updates for Haneda, as sudden shifts in cloud cover or wind patterns can push temperatures toward the 31–32°C threshold before the settlement window closes at 12:00 UTC on 10 July.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Tokyo on July 10? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi Alternative UK, which mirrors the Polymarket order book at 0% fees.

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

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.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

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

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Kalshi Alternative UK 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.