Highest temperature in Paris on July 3?

Platform comparison

Market context

The highest temperature recorded at Paris-Le Bourget Airport on 3 July 2026 is expected to fall within the 28°C range, as the market currently prices this outcome at 78% probability, while the "YES" option for any temperature exceeding the settlement threshold sits at 0% [1]. This on-chain contract, settled in USDC on the Polygon network using conditional tokens, reflects a consensus that the day will be intensely hot but not record-breaking in the extreme sense implied by the zero-probability "YES" side.

Historical precedents from the 2026 European heatwaves show that Paris has already experienced temperatures near 41°C in previous weeks, with national thermal indicators reaching record highs of 29.8°C [4][5]. However, recent forecasts for 3–4 July indicate a powerful heatwave pushing temperatures to 36–37°C in Paris, with morning lows around 22–23°C and dry conditions dominating [2][3]. The current 78% probability for 28°C suggests traders are weighing the likelihood of a peak just below the 30°C threshold, despite the broader heatwave context.

Traders should monitor Météo France’s daily updates and Wunderground’s real-time data for the Paris-Le Bourget station, as the settlement relies exclusively on the highest temperature recorded for all times on that day [1]. Recent news from Le Monde confirms a third heatwave is expected to hit the Paris region this weekend, with temperatures potentially reaching 36–38°C [3]. Any deviation from the 28°C forecast—such as a sudden spike above 30°C—would shift the probability distribution, but current on-chain pricing remains anchored to the 28°C outcome.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Kalshi UK, which mirrors the Polymarket order book directly.

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

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

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.

Do I need to KYC for this market?

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