Highest temperature in Paris on July 3?

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Market context

Paris is bracing for a powerful heatwave today, with temperatures sharply rising well above seasonal averages across northern France as a third heat episode of the year begins. The crowd-implied 0% probability for the highest temperature in Paris on July 3 now looks starkly misplaced after forecasts updated in the last 24 hours, predicting afternoon peaks of 36°C to 37°C at Paris-Le Bourget, with midday spikes potentially reaching 38°C. This rapid shift from a cool expectation to scorching reality means the market has failed to price in the immediate intensity of the current atmospheric conditions.

Historically, Paris has rarely seen July highs this severe, yet the June 2026 heatwave set a new benchmark with a record 40.9°C in Paris on 23 June, the hottest day since 1947[2]. That event proved the city’s vulnerability to extreme early-summer heat, making a 36°C+ day on July 3 plausible rather than impossible. The current 0% probability ignores this precedent, treating the event as an outlier despite the clear pattern of escalating heatwaves in 2026, where France has already recorded its three hottest days in history[4].

Traders should monitor Météo-France’s orange alert reactivation schedule and the weekend temperature climb forecast, which warns of peaks up to 38°C–40°C in the Paris region[4]. The key dependency is the northward spread of the southern heatwave, with climatologist Davide Faranda predicting a peak next Wednesday through Friday[4]. Recent updates from Le Monde confirm temperatures will fall briefly on Thursday before climbing again on Friday, directly aligning with the settlement window[4]. Watch for real-time Wunderground data at Paris-Le Bourget, as the market resolves on the highest recorded temperature for all times on 3 July.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

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FAQ

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