Overview
- Meteorologists say Tuesday will deliver an exceptional late‑September heat peak with widespread highs around 26–33°C and possible national record values cited by multiple services.
- A large Atlantic depression is forecast to cross France Wednesday–Thursday and bring a relatively sudden, durable drop in daytime maxima of roughly ten degrees in some areas.
- Model guidance and specialists highlight a focused risk of very heavy rain from the golfe du Lion through the basse vallée du Rhône into parts of the Cévennes where 100–200 mm could fall locally in a short time.
- Météo France has warned of particularly heavy storms in Languedoc‑Roussillon with orange vigilance under consideration because short, intense Mediterranean-type ('episode cévenol') rainfall can trigger rapid flash floods on confined valleys.
- Even if midweek rains are intense, they are unlikely to erase the wider spring‑to‑summer drought and soils will stay dry in many places which means farmers and local authorities should still plan for lingering water stress and runoff-driven flood risk.