Highest temperature in Beijing on August 3?

Platform comparison

Market context

The event is whether Beijing Capital International Airport’s highest temperature on 3 August will land in the contract’s winning Celsius band, and the market is already pricing that outcome as effectively impossible, with crowd-implied probability at 0% YES. That is notably lower than the broad weather picture: short-range forecasts for Beijing on 3 August cluster around the low- to mid-30s Celsius, with one official city forecast putting Beijing at 25–32°C and others showing around 33–37°C for the day, which would leave the eventual airport high well inside the ordinary summer range rather than at an extreme[2][3][6][7].

Historically, Beijing in August is hot but variable, with typical highs around 31–32°C and frequent rain or thunderstorms that can cap the daytime peak if cloud cover arrives early[5][8][15][16]. That makes the key question less about whether Beijing is warm and more about whether convection develops before the day’s maximum is set; airport readings can run a little cooler or hotter than city-centre forecasts depending on timing of showers, wind direction and sunshine duration. On those comparables, a 0% market-implied chance looks far below the forecast consensus and the historical baseline, suggesting a pronounced divergence between prediction-market pricing and mainstream weather expectations[2][6][7][15].

For traders, the main catalysts are the final 24–48-hour forecast runs and any shift in thunderstorm timing, because a morning or early-afternoon shower can compress the high while a clearer window can push it up by a degree or two. There is no sportsbook-style line here to arbitrate, so the useful comparison is between the market’s zero pricing and the weather services’ expectation of a normal hot August day; analyst-style consensus from the available forecast pages sits much closer to the low-30s Celsius than to any extreme outcome[2][3][6][9].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Beijing on August 3? 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

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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi vs Polymarket trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.