Highest temperature in Chengdu on July 20?

Platform comparison

Market context

Chengdu recorded its peak July 20 temperature at the Shuangliu International Airport Station, with the market now resolving to the specific Celsius range. Historical data shows July afternoon highs in Chengdu typically reach 33°C, though they can climb to 35°C during warmer spells, with 20 rainy days averaging 188mm of rainfall [2][3]. The current crowd-implied probability of 0% for any outcome above the lowest range contradicts the Polymarket frontrunner, which assigns 100% probability to 38°C, suggesting a stark divergence in how platforms interpret the same meteorological baseline [1].

Traders comparing Polymarket against Kalshi, Betfair, or Smarkets should note that Polymarket displays outcomes as implied probabilities while competitors often use decimal odds, creating friction when assessing value on this specific weather event. Fee structures and KYC requirements also vary significantly; Polymarket generally offers lower barriers to entry than Kalshi’s strict US-only KYC, while Betfair and Smarkets operate under different regulatory frameworks that may limit access for certain users. The 38°C frontrunner on Polymarket appears an outlier against the 30–35°C historical norm, indicating either a data error or a unique market sentiment not reflected in traditional weather books [1][2].

No immediate catalysts such as official heatwave announcements or schedule changes are expected to alter the settlement, as the resolution relies solely on Wunderground’s recorded daily maximum for ZUUU. The market closes at 12:00 UTC on 20 July 2026, locking in the final temperature reading regardless of subsequent forecasts. Given the 2026 date and the current 0% probability for higher ranges on some platforms versus 100% on Polymarket, the discrepancy highlights how platform-specific liquidity and user behaviour can distort implied probabilities on identical real-world events [1][2].

Sources: 1 · 2 · 3 · 4

Methodology

We read Highest temperature in Chengdu on July 20? from four platform perspectives: Polymarket (on-chain CLOB), Kalshi (CFTC-regulated exchange), Betfair Exchange (sports book exchange), Smarkets (peer-to-peer betting exchange). Polymarket's live mid is the canonical probability; the side-by-side columns benchmark fees, KYC, settlement currency and deposit rails so you can choose the venue that fits your jurisdiction and trade size.

Resolution & payout

Settlement is the biggest difference between the four platforms: Polymarket on-chain in USDC (instant), Kalshi USD via CFTC (T+1), Betfair and Smarkets in local currency via bank withdrawal (T+1 to T+3). On-chain settlement clears in minutes — the fastest payout path of the four.

FAQ

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

What about Smarkets as an alternative?

Smarkets is a UK betting exchange with a lower default commission (2%) than Betfair. Liquidity on political markets is below Polymarket, comparable to Kalshi. Geo-blocked in many jurisdictions.

Which platform is accessible globally?

Polymarket is geo-blocked in the US/UK/EU. Kalshi is US-only. Betfair and Smarkets are UK-restricted. Kalshi Alternative has a different geo footprint and routes to Polymarket's order book at 0% fees.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Kalshi Alternative offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.