France’s national weather service, Météo-France, confirmed on 18 July that the country’s latest heat episode is retreating toward the Mediterranean basin but will continue to disrupt travel and outdoor work. Day-time highs of 39 °C are forecast for Marseille, Nice and Montpellier through Monday, while night-time temperatures are expected to remain above 24 °C—conditions that strain rail tracks, tarmac and power infrastructure. Although northern regions including Île-de-France saw a slight temperature dip overnight, SNCF said speed restrictions would stay in place on several high-speed and regional lines until sensors show rail temperatures below 50 °C. The operator has warned customers of potential delays of up to 45 minutes on Sunday services connecting Paris with Lyon and Bordeaux. Airlines at Paris-CDG reported minor schedule adjustments as ground-handling crews invoked hot-weather safety protocols that limit consecutive exposure times. Employers with staff on assignment in the Rhône valley and Provence should review their heat-stress policies. Construction sites in the Marseille port district have already shifted to split-shift timetables, and local labour inspectors conducted spot checks on 17 July to ensure compliance with mandatory rest-water-shade rules. Foreign assignees unfamiliar with French employment law should note that failure to provide appropriate protective measures can trigger immediate site closures. For travellers, the most visible impact will be on road traffic. The French road agency Bison Futé upgraded several segments of the A7 (‘Autoroute du Soleil’) to red status for north-south flows on 19 July, citing a combination of holiday traffic and heat-related vehicle breakdowns. Drivers are advised to travel during cooler early-morning hours and to carry at least three litres of water per person. While the current event is less extreme than the record-shattering heatwave of June 2025, it is the first major test of new heat-adaptation measures introduced by French transport operators this year. The next 48 hours will show whether reinforced rail joints, reflective road coatings and staggered work schedules can keep essential mobility corridors functioning under prolonged thermal stress.
Source: Météo-France
