Highest temperature in Tokyo on August 7?

Platform comparison

Market context

Tokyo’s highest temperature will be set by the day’s actual reading at Haneda Airport, not the broader Tokyo summary figure, so the market is effectively a single-station daytime heat call for 7 August. August is typically Tokyo’s hottest month, with average highs around 31°C and frequent excursions into the low-to-mid 30s, and both AccuWeather and other August guides point to values around 88°F/31°C for early August this year[1][4][10]. JMA’s Tokyo-area August data already shows several stations pushing well above 35°C on comparable dates, while Haneda itself has been tracking lower than inland sites such as Nerima or Hachioji, which matters because the contract settles on the airport station only[2].

That station-specific setup helps explain the current 0% implied YES: on a noon UTC settlement window, traders are likely using the lack of an observed reading yet, or a missed tick in the market book, rather than a genuine expectation of a sub-zero outcome. Historical August heat patterns in Tokyo usually support a result somewhere in the 30–35°C band, with forecast services flagging 7 August at roughly 88°F/31°C and broader travel guides warning that daytime spikes above 30°C are normal in peak summer[1][5][8]. By contrast, a *Polymarket* quote is typically read as implied probability, while *Kalshi* and *Smarkets* often show price in cents or decimal-style terms, so a “0%” signal can mask a wide range of operational frictions rather than a true market consensus.

For catalysts, the main drivers are the final Haneda Airport observation sequence on Weather Underground and any late-day heat spike tied to the Pacific High, which Japanese seasonal outlooks have said is likely to keep summer 2026 warmer than normal[12]. A trader should also watch for any adjustment to station data availability on Wunderground, because this market explicitly resolves from the Daily Observations table. Platform mechanics matter here too: Betfair-style exchange trading can offer tighter depth but requires KYC access and applies exchange commission, while Smarkets and Kalshi usually quote in different price formats and fee structures, so the same weather view can display as very different market language even when the underlying temperature thesis is identical.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read Highest temperature in Tokyo on August 7? 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.

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. Robinhood Prediction Markets 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. Robinhood Prediction Markets 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.