French weekly weather forecast July 27 - 31: fourth heatwave arrives, highs of 40C

France is bracing itself for a record fourth heatwave to arrive this week, bringing temperatures of up to 40C to the south-west and central areas. 

Following a drop in temperatures over the weekend, a rapid climb will see highs of 40C possible as early as Wednesday (July 29). 

By Wednesday night, overnight temperatures of 20C or more (nuits tropicales) are expected across most areas save the northern coastline, rising to 23C and above in Paris, the Riviera and the Rhône Valley.

Current forecasts predict that the heatwave may last until at least Wednesday, August 5. 

This is the first time on record that France will face four official heatwaves across a single summer.

Monday July 27 

The week starts calm and sunny, with temperatures only slightly above average. 

It follows a weekend of storms in the south that brought rainfall to several areas, cooling temperatures and dampening vegetation in light of major wildfires. 

Highs of 25C - 27C in the north are forecast, up to 30C in the south and potentially 33C in Provence. 

Tuesday July 28 

Temperatures will quickly begin to climb on Tuesday, reaching above 30C in most of the north and up to 35C in the south-west. Some areas may even see highs of 37C. 

Conditions will again be sunny and clear, making it feel warmer than the thermometer states (official temperatures give readings in the shade). 

Overnight temperatures will already begin reaching 20C and above in many areas. 

Wednesday July 29 

Temperatures will continue to climb, reaching up to 40C across much of western and central areas. 

Highs of 35C and above across the north near Paris and in the east are also expected, with the national average temperature reaching 28.1C, more than 6C above typical for the season. 

This is around the same as the end of the mid-July heatwave.

State forecaster Météo France only issues weather warnings one day in advance meaning information for midweek is not yet available, but it is possible that official heatwave alerts will be issued by Wednesday, particularly in the south-west and centre. 

High overnight temperatures will contribute to the arrival of heatwave warnings, with minimum thresholds needing to be reached before departmental alerts are declared. 
There is no indication yet of how severe warnings will be, but the duration of the heatwave means it is possible that red-level alerts are eventually implemented. 

Thursday July 30 

Temperatures of up to 40C remain possible across most of the country, particularly the inland south-west and centre. 

Coastal areas will remain slightly cooler, but only the tip of the Breton and Cotentin peninsulas seeing temperatures below 30C. 

Storms are currently forecast in the evening around the Pyrénées, but are set to be brief and unlikely to impact the wider heatwave. 

Friday July 31 

A small reduction in temperature is forecast on Friday, although it will remain well above typical for the season. 

Temperatures will remain at around 30C in the north, and 32C in the south-west and Riviera. 

Central and eastern areas as well as the Rhône Valley may see highs of 35C and above, despite rain forecast throughout the area in the afternoon.

Early forecasts predict rain to continue to fall across the east and south-east throughout the weekend, without affecting temperatures. Elsewhere, temperatures may begin to rise once more.