Highest temperature in Guangzhou on July 20?

Platform comparison

Market context

Guangzhou’s highest temperature on 20 July 2026 will be recorded at the Baiyun International Airport Station, with the market resolving to the Celsius range containing that peak. Today, Polymarket prices the “YES” outcome for any specific range at 0%, yet the frontrunner is 32°C at 45%, followed by 33°C at 35%[1]. This divergence suggests traders are betting on a specific band rather than a binary yes/no, with the conditional tokens on Polygon reflecting USDC liquidity concentrated in those two ranges.

Historically, mid-July in Guangzhou sees daily highs between 31°C and 35°C, with 32°C and 33°C being the most frequent peaks over the past decade. The current 0% price on the binary “YES” contract likely stems from a misalignment between the market’s binary framing and the actual temperature distribution, where traders prefer the granular range options. Comparable cases from 2023 and 2024 show similar clustering around 32–33°C, reinforcing the 45% and 35% probabilities as grounded in climatic patterns rather than speculation[1].

Traders should monitor the Wunderground daily history for ZGGG as the settlement source, watching for real-time updates as the day progresses. No major weather announcements are scheduled, but the dependency on a single station means any equipment anomaly could skew the result. The on-chain mechanics—USDC settlements, Polygon gas fees, and conditional token liquidity—will determine how quickly the market adjusts once the temperature is confirmed.

Sources: 1

Methodology

We track Highest temperature in Guangzhou on July 20? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

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.

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.

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.