Highest temperature in Tokyo on August 10?

Platform comparison

Market context

Tokyo’s hottest reading on 10 August will come from the Haneda Airport station and will be settled against Weather Underground’s **Daily Observations** table, not the headline “Day High & Low” figure. That matters because the market is about the *single highest recorded temperature* in Celsius on the day, so short-lived afternoon spikes or a late update can change the outcome even if the summary panel looks stable.

On comparable mid-August Tokyo days, the city’s highs are usually in the low-to-mid 30s Celsius, with recent historical sources showing August averages around 31°C and several recent 10 August readings in the 34–37°C range. Weather Underground’s Tokyo history page also shows an August record high of 100°F on its history summary, while JMA climate tables and other archives indicate that extreme heat is plausible but not routine, which helps explain why the current 0% implied chance looks detached from the seasonal baseline rather than a settled meteorological expectation.

For traders, the key catalysts are the day’s actual observations and any late updates on the Weather Underground station feed; there is usually no ex ante “announcement” risk, but a rapid rise in heat index, a clear-sky afternoon, or delayed station reporting can move the final print. On platform mechanics, Polymarket-style pricing is often quoted as an implied probability, whereas Kalshi and some exchange-style books show prices closer to a tick or decimal-style contract value; fee treatment also differs, with exchange fees and market-maker spreads affecting executable price more than the headline number. KYC access is another divider: Kalshi and Smarkets generally require full identity checks in their eligible jurisdictions, while Betfair access and market availability vary by region and product, which can make cross-platform comparison uneven on a location-specific weather market.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read Highest temperature in Tokyo on August 10? 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.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

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 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. Kalshi 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.