Highest temperature in Guangzhou on August 4?

Platform comparison

Market context

Guangzhou’s airport reading is the number that matters here: the market resolves to the day’s highest temperature at Guangzhou Baiyun International Airport Station on 4 August, so a city forecast is only a guide if the airport behaves similarly. The current crowd-implied 0% YES on a temperature-range market usually indicates the present price is sitting outside the range that traders think is most likely, rather than that the event is impossible; with local August forecasts clustering around the low 30s Celsius, the distribution is plainly in play.[1][2][3]

That context matters when comparing books. On Polymarket, a market price is shown as an implied probability, so a 0% quote typically means the “yes” side is priced at the floor; Kalshi and Betfair display prices differently, with Kalshi using dollar-based contracts and Betfair quoted odds, while Smarkets uses decimal odds and an exchange commission model. For this kind of weather market, the practical divergence is less about the forecast itself than about costs and access: exchange-style books can be more transparent on spreads and fees, but KYC coverage and regional availability differ materially by venue, which affects who can participate and how tightly the price can track late weather updates.

The main catalysts are short-horizon forecast revisions, rain-band timing, and any shift in cloud cover or sea-breeze effects that could cap the daytime high at the airport. Official regional guidance issued this morning put Guangzhou at 25–32°C, with nearby stations ranging higher, which is consistent with a warm but rain-affected day rather than a clean breakout above the mid-30s.[2] Airport observations also matter because Baiyun readings can lag inland highs; a humid, showery pattern can keep the day’s peak near the low 30s even if surrounding districts briefly run hotter.[8][18]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page compares Highest temperature in Guangzhou on August 4? 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 Robinhood Prediction Markets, 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

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.

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. 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.