Highest temperature in Guangzhou on August 21?

Platform comparison

Market context

On 21 August 2026, the highest temperature recorded at Guangzhou Baiyun International Airport will determine this market's resolution. The settlement window closes at midday UTC on that date, with Weather Underground's Daily Observations table serving as the authoritative source rather than the Day High & Low summary section—a distinction that matters when discrepancies arise between the two datasets.

Guangzhou's August climate presents consistent thermal patterns. Historical data from the past decade shows daily highs in August typically range between 32–35°C, with occasional peaks exceeding 36°C during heat waves. The 0% crowd-implied probability currently priced into this market suggests traders are either awaiting specific temperature thresholds to be defined or treating the contract as incomplete pending clarification on which temperature range constitutes the YES resolution. Comparable August markets in subtropical Chinese cities have seen meaningful probability shifts once temperature bands are specified; ambiguity about the exact threshold has historically suppressed trading activity.

Traders monitoring this contract should track China Meteorological Administration forecasts released in early August 2026, which typically provide 10–14 day outlooks for Guangzhou. The timing of any tropical cyclone activity in the South China Sea during late August could materially affect local temperatures. Additionally, the specific resolution mechanics—reliance on Baiyun Airport station data rather than urban centre readings—means traders should verify historical temperature differentials between that location and downtown Guangzhou, as the airport site often records slightly lower maxima due to proximity to water bodies and airfield characteristics.

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Best Prediction Markets, which mirrors the Polymarket order book directly.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Best Prediction Markets. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.