Highest temperature in Beijing on July 31?

Platform comparison

Market context

Beijing Capital International Airport is in the middle of peak-summer weather on 31 July, when the city’s typical July daytime high is around 31°C and the month is both hot and rain-prone. Historical July summaries show plenty of headroom above that average, with Beijing’s recent monthly extremes reaching 40°C in 2023 and a broader historical high of 41.6°C in the 2016–2025 dataset, so the market’s 0% implied “YES” price is only sensible if traders think airport-specific July 31 heat will stay well below the relevant bucket. [1][2][3]

For comparison-style reading across venues, Polymarket and Kalshi usually present probability directly, while Betfair and Smarkets show decimal odds, so a 0% probability on one platform can still correspond to a very long-priced but non-zero trade elsewhere once commission is included. The important local detail is that this contract resolves from the highest temperature at Beijing Capital International Airport Station on the calendar day, not the city’s headline forecast or a neighbourhood reading, so a trader needs to anchor to airport observations and the exact settlement cut-off rather than to broad Beijing averages. [2][4]

The main catalysts are straightforward: the day’s synoptic pattern, any afternoon convection or thunderstorm line, and whether the airport station posts a late peak before the market’s 12:00 UTC settlement window closes. Beijing July climate references point to frequent rainfall and thunderstorms, which can cap the day’s maximum even when morning values are already warm; as a result, the key watch item is not whether Beijing is hot in general, but whether the airport records a reading inside the contract’s temperature band before midday UTC. [1][12][18]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read Highest temperature in Beijing on July 31? 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.

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.

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 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.