Highest temperature in Guangzhou on July 1?

Platform comparison

Market context

The real-world event concerns the highest temperature recorded at Guangzhou Baiyun International Airport on 1 July 2026, measured in degrees Celsius. Current crowd-implied probability for a specific outcome sits at 0%, yet Polymarket data shows "35°C" as the frontrunner at 38%, with "36°C" trailing at 25%. This divergence highlights how platforms like Polymarket display decimal odds alongside implied probabilities, whereas Kalshi and Betfair often emphasise one metric over the other, creating distinct trading signals for the same weather event. Fee structures also vary; Polymarket typically charges lower fees than Smarkets, while Kalshi enforces stricter KYC requirements that limit global access compared to the more open registration on Polymarket.

Historical records frame this market with significant weight, as Guangzhou reached 39.1°C on 1 July 2004, the highest temperature ever recorded in the city[4]. July is consistently one of the hottest months, with daily highs averaging 91°F (33°C) and rarely falling below 85°F[2][7]. Recent climate data confirms China experienced its hottest July on record in 2024, with average temperatures eclipsing previous decades[3][6]. Traders should monitor upcoming weather forecasts and any announcements regarding heatwaves, as rising global temperatures suggest a higher likelihood of extreme heat events in 2026. Reuters reported that July 2024 temperatures averaged 23.21°C, setting a new benchmark for recent history[6].

Key catalysts include the release of daily weather data from Wunderground, which serves as the official resolution source for this market. Traders must watch for scheduled meteorological updates and any government announcements on extreme heat warnings in Guangdong province. The settlement window ends on 1 July 2026 at 12:00 UTC, requiring precise timing for position adjustments. Differences in data latency between platforms may create arbitrage opportunities, particularly if Polymarket updates odds faster than Kalshi. Understanding these platform-specific dependencies is crucial for navigating the market effectively without relying on moralising advice about whether to trade.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We read Highest temperature in Guangzhou on July 1? 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

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.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

Which platform is accessible globally?

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