Highest temperature in Shenzhen on July 6?

Platform comparison

Market context

Shenzhen will experience its peak daytime heat on 6 July 2026, with the highest temperature recorded at the Bao'an International Airport Station determining the market outcome. Today, Polymarket prices the "31°C" contract at 0% YES, implying the crowd believes this threshold is virtually impossible to breach, while the "32°C" outcome dominates recent sentiment.

Historical data frames this near-zero probability as a misreading of local climatology. July is Shenzhen’s hottest month, with average highs reaching 32°C (90°F) and frequent spikes to 35°C (95°F) during subtropical high pressure events [1][8]. Recent on-chain settlements confirm this trend: the 4 July market resolved at 31°C with 100% certainty, and the 5 July market settled at 32°C with 91% confidence [2][3]. The current 0% price for 31°C ignores that temperatures have consistently exceeded this baseline in the immediate past.

Traders must monitor the subtropical high’s position and incoming typhoon forecasts, as these dictate whether heavy showers suppress the heat or clear skies allow extreme warming. The settlement relies on Wunderground data from the Bao'an station, making real-time weather updates critical for conditional token valuation on the Polygon network [1]. While no specific announcement has altered the forecast yet, the 340mm monthly rainfall average suggests a single rain event could shift probabilities from the current frontrunner [1]. USDC liquidity remains deep, but the 0% entry price offers no upside unless the market corrects its underestimation of July’s typical thermal ceiling.

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

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

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.

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.