Highest temperature in Beijing on July 24?

Platform comparison

Market context

Beijing’s heat on 24 July will be set by the day’s maximum at Capital International Airport, so the key question is not whether it is summer-warm, but whether the airport reaches a *particular bracket* before the settlement window closes. July is Beijing’s hottest month, with typical daytime highs around 31°C and the possibility of 38-40°C during stronger heat spells, while humidity and thunderstorms can make conditions swing sharply within a single afternoon.[1][2]

The 0% YES crowd view looks conservative against the seasonal baseline, but that figure is only meaningful if the market’s target bracket is well above the more usual July peak. For comparison, Polymarket shows this event in 11 outcome bands and translates the book directly into implied probabilities, whereas Kalshi-style contracts are typically quoted in cents and implied probabilities are inferred from price; Betfair and Smarkets instead use decimal-style trading with visible commission, so the same weather view can look cheaper or richer depending on how fees and spread are shown. The practical read is that Beijing’s July climatology favours mid-30s readings, yet a specific airport observation can still settle below a hotter city-centre expectation.[1][3][4]

Traders should watch for midday solar heating, cloud build-up, and any convective rain that suppresses the daily high before it is recorded at the airport station. Beijing’s rainy season often intensifies in late July, with showers and thundershowers common, and that matters because cloud cover can cap the maximum even on a very hot day.[1][2] If the market is still open close to the US morning, the live airport observation path, rather than city forecasts alone, will be the decisive catalyst for repricing.[4]

Sources: 1 · 2 · 3 · 4

Methodology

This page compares Highest temperature in Beijing on July 24? 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, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

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.

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.

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.

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.