Highest temperature in Chengdu on August 9?

Platform comparison

Market context

Chengdu’s maximum temperature on 9 August is usually set by a hot, humid afternoon rather than the morning reading that is visible early in the day. Long-run August averages for Chengdu sit around 30-31°C for highs, with typical warm-season peaks in the low-to-mid 30s Celsius, and historical extremes have reached about 39°C in the city, so the market should be read as a fairly standard summer heat outcome rather than a tail event.[14][17][7]

That said, the current 0% YES implies the quoted range is not matching the live weather path at Chengdu Shuangliu International Airport Station. Weather Underground’s station history showed 79°F at 9:00 AM local time, with the daily observations table designated as the primary source for settlement; because the market resolves to the highest observed temperature in that table, traders need the day’s full afternoon trace rather than the summary high/low box.[3][12] On Polymarket, this contract is quoted in implied probability, while Kalshi, Betfair and Smarkets typically expose the same event through decimal-style pricing and different fee or commission structures, and KYC reach varies by venue and jurisdiction, so the same temperature view can translate into very different headline prices.[12]

For catalysts, the key watchpoint is the evolution of the station’s hourly observations through the local afternoon, especially any surge into the mid-30s Celsius if sunshine breaks through cloud cover. Chengdu forecasts for 9 August pointed to cloudy conditions and around 33°C, with the next day forecast a little hotter, which suggests the final print could still move if convection weakens or a drier air mass develops later in the day.[20][15] Internationally, compare how each book handles fees: Polymarket’s market price is the cleanest read on consensus, whereas Betfair and Smarkets factor in commission, so a 34°C outcome can look cheaper or dearer on screen even when the underlying expectation is similar.[12]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read Highest temperature in Chengdu on August 9? 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.

UK Frequently Asked Questions

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

What does Polymarket cost vs Kalshi?

Polymarket: 0% fees, only Polygon network costs (~$0.01/trade). Kalshi: up to 7% per trade plus spread. For high-frequency traders, Polymarket is dramatically cheaper.

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.

Polymarket vs Betfair Exchange: which is better for UK prediction trading?

Betfair Exchange offers UKGC regulation, GBP settlement, and potentially tax-free winnings — but focuses on sports and politics only. Polymarket has deeper liquidity, 0% platform fee, global event coverage, and crypto/geopolitical markets Betfair doesn't offer. For UK traders: Betfair for regulated GBP sports markets; Polymarket for broader, global prediction events.

Is Kalshi available in the UK?

Kalshi is a US CFTC-regulated prediction exchange. UK residents can create accounts but must use USD and US payment methods. Kalshi's product range overlaps with Polymarket but with lower liquidity on most contracts. For UK traders, Polymarket typically offers better prices due to higher global volume.