Highest temperature in Shanghai on July 4?

Platform comparison

Market context

The underlying real-world event is the peak temperature recorded at Shanghai Pudong International Airport on 4 July 2026, measured in degrees Celsius. Current Polymarket pricing shows a 0% implied probability for the "YES" outcome, suggesting the market expects the temperature to fall outside the specific range being traded. This stark valuation contrasts with historical patterns where July in Shanghai routinely features extreme heat, with roughly 7 to 15 days per month exceeding 35°C (95°F) [3]. Recent climate data confirms China experienced its hottest summer in 60 years, with temperatures reaching a preliminary high of 40.9°C at the Xujiahui station in Shanghai [4][8]. The 0% price likely reflects a narrow range definition rather than a lack of heat, as average daily highs in July often reach 32°C to 35°C, with peaks occasionally soaring higher [1].

Traders should monitor the official meteorological schedule for Shanghai and any sudden announcements regarding heatwave warnings or ozone plagues, which frequently accompany extreme temperatures in the region [4]. The settlement depends entirely on Wunderground data for the Pudong station, so traders must watch for potential data gaps or sensor anomalies that could delay resolution before the 2026-07-04T12:00:00Z deadline. While China recorded its hottest month in recent history in July 2024, averaging 23.21°C, the daily peaks in Shanghai are significantly higher than this monthly average [2]. On-chain mechanics using USDC on the Polygon network mean conditional tokens will resolve automatically once the official temperature is logged, making real-time weather feeds the primary catalyst for position adjustments.

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

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 Polymarket Legit?. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 Polymarket Legit? 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.