Highest temperature in Guangzhou on July 7?

Platform comparison

Market context

The real-world event driving this market is the peak temperature recorded at Guangzhou Baiyun International Airport on 7 July 2026, measured in degrees Celsius and sourced from Wunderground. Historical data shows July highs in Guangzhou typically hover around 33°C (91°F), rarely dipping below 30°C or exceeding 36°C, with the highest average daily high occurring on 25 July at 33°C[2]. Recent records confirm China experienced its hottest July since 1961, with an average of 23.2°C across the month, suggesting a trend toward elevated heat[3]. The current 0% YES probability implies the market expects the temperature to fall outside the specific range being bet on, likely because 34°C is already treated as a one-in-four chance for 3 July, making an identical peak on 7 July statistically less probable[1].

Traders should monitor daily weather bulletins from the China Meteorological Administration and Wunderground’s hourly updates for the Baiyun station, as thunderstorms with heavy rain are common in early July and can suppress peak temperatures[4]. A recent Reuters report highlights that China recorded its hottest month in recent history in July 2024, with temperatures averaging 23.21°C, reinforcing the likelihood of continued heat anomalies in 2026[8]. Programmatically, a power-user would deploy a script to poll Wunderground’s API every hour on 7 July, cross-referencing with PredictWind’s historical records for Guangzhou Shi to validate anomalies before executing conditional orders[7]. The settlement window closes at 12:00 UTC on 7 July 2026, so latency in data ingestion could impact copy-trading bots relying on real-time feeds.

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

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.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

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.