Highest temperature in Shanghai on July 20?

Platform comparison

Market context

Shanghai Pudong International Airport is currently recording 31°C with a 90% chance of precipitation and local thunderstorms expected this afternoon, making a zero-probability YES price for any high-temperature outcome appear mathematically sound given the active cloud cover and rain risk [2][3]. The market, trading in USDC on Polygon via conditional tokens, reflects this immediate atmospheric reality where the settlement window closes at 12:00 UTC tomorrow, leaving little time for a heat spike to override the current wet pattern.

Historical July data for Shanghai typically sees highs between 33°C and 37°C, yet the current 0% implied probability for high ranges aligns with the specific 70% precipitation chance and mostly cloudy conditions forecast until noon, which suppress surface heating significantly compared to dry, sunny counterparts [3]. Traders reviewing the lowest temperature market see a frontrunner at 27°C with 100% certainty, reinforcing the consensus that the day will remain muggy rather than scorching, a pattern that historically invalidates bets on extreme heat when rain systems are present [1].

Key catalysts to watch include the timing of the afternoon thunderstorms and the wind shift from South to Southwest, as any delay in precipitation could allow temperatures to climb, though the high chance of rain currently dominates the forecast [3]. No official government announcements or schedule changes are pending that would alter the weather station’s operation, meaning the resolution relies entirely on the real-time Wunderground data feed for the Shanghai Pudong station [1]. The on-chain mechanics ensure that once the 12:00 UTC deadline passes, the conditional tokens will settle automatically based on the recorded peak, with the current weather trajectory heavily favouring the lower temperature brackets.

Sources: 1 · 2 · 3 · 4

Methodology

We track Highest temperature in Shanghai 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

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 PolyGram. 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 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.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram 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.