Highest temperature in Guangzhou on July 27?

Platform comparison

Market context

Guangzhou’s Baiyun airport needs to print the day’s highest reading by the 12:00Z settlement cut-off, and the crowd-implied **0% YES** makes the market a strong favourite against any hot-day outcome. On the current weather picture, Guangzhou is already sitting in the high-20s Celsius before the local afternoon heat builds, with forecast highs clustered around **34–37°C** and only limited rain risk, which argues that the consensus is leaning heavily towards a warm-to-hot result rather than an outlier cool reading.[1][5][6]

For framing, the comparable case is simple: when a tropical South China city is forecast to be partly cloudy but still humid, the main question is usually not whether it gets warm, but how far the airport sensor runs before cloud cover or showers cap the peak. That leaves the **favourite** side firmly with “a high above the lower brackets”, while the **underdog** angle is a late-morning rain band, sea-breeze suppression, or a timing issue that leaves the official maximum below the market’s more aggressive heat expectations.[1][2][3]

The catalysts traders should watch are the near-term Guangzhou forecast updates, especially any shift in precipitation probability or cloud cover before the airport’s hottest part of the day, plus local wind and humidity changes that can trim the maximum. The consensus value appears to sit with the *higher* temperature ranges if the current dry-and-warm forecast holds, while the contrarian case is a lower peak if showers materialise or the heat tops out earlier than expected; recent daily forecasts already differ on the exact ceiling, which is typical for a live weather market of this kind.[1][2][4][6]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Who Will Win. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.