Highest temperature in Paris on July 3?

Platform comparison

Market context

Paris is bracing for a powerful heatwave on 3 July 2026, with temperatures expected to surge well above seasonal averages across northern France. Forecasts indicate afternoon highs reaching 36–37°C at Paris-Le Bourget, while southern France could see 38–41°C, driven by intense sunshine and dry conditions limiting overnight cooling. This real-world event underpins the market’s 0% YES probability for lower temperature ranges, as current data strongly points to extreme heat.

Historically, early July heatwaves in France have frequently breached 35°C in Paris, with the 2022 and 2023 events setting records near 40°C. The 2026 European heatwaves, documented as the most severe of the year, show similar patterns: Meteo France issued red alerts for 54 departments in June 2026, with temperatures hitting 42°C in hotspot areas. These comparable cases frame the current probability as a near-certainty for high ranges, not a speculative outlier.

Traders should monitor Meteo France’s daily bulletins and the El Niño-driven weather model updates, which forecast this heatwave lasting 7–10 days. A recent Reuters report (19 June 2026) confirms temperatures could reach 37–42°C starting Sunday, with Paris experiencing 35–38°C. Programmatically, conditional orders tied to Wunderground’s hourly data feeds would capture real-time shifts, while copy-trading bots tracking high-volume Paris heat contracts could exploit thin liquidity in this market. The settlement window ending 12:00 UTC on 3 July ensures resolution aligns with peak afternoon readings.

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

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.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

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.