Southern France braces for intense rain: up to 250mm forecast

Meteorologists have forecast intense rain in the south of France this week, with up to 250mm expected to fall in some areas. 

Original forecasts for this week saw persistent rain in the south, with the threat of stormy weather on Thursday. 

While these storms are still expected, the amount of precipitation forecast before this has greatly increased, and is set to arrive earlier than first believed. 

The weather pattern bringing the rain is expected to be a classic épisode méditerranéen.

This sees warm air carrying rain clouds moving in from the sea blocked by inland highlands and mountains, subsequently dropping much of the rain along coastal areas (or in some cases, mountain valleys).

In extreme cases, several months’ worth of rain can fall within a few hours or days.

The phenomenon often results in flooding, as rain becomes concentrated in a small area due to clouds remaining stationary.

A powerful épisode méditerranéen on October 19 - 20 saw four people die in south-east France due to the heavy rains and flooding.

The downpour will do little to replenish water tables in the area, as the intensity of the rain will see soils quickly saturated and unable to take on more water.

Rain from tonight 

Forecasters now expect rainfall to begin overnight, before increasing in intensity on Wednesday (November 4) morning. 

Rain will begin around Hérault, spreading to the neighbouring Gard and Aude departments, with the Bouches-du-Rhône department also impacted. 

There is no certainty over how far the rain will penetrate, and state forecaster Météo France warns it could reach as far north as central Limousin and Auvergne. 

Rain is expected to fall continuously until Thursday evening, intensified by the potential appearance of stormy conditions on Thursday morning and strong winds in the Gulf of Lion from Wednesday. 

Across this period, between 200mm - 250mm of rain is forecast to fall in areas of the departments listed. 

Météo France is expected to issue heightened weather alerts for the conditions on Wednesday and Thursday.

Currently, only tier-two ‘yellow’ alerts for heavy rain/flash-flooding and storms are in place from Wednesday morning, and with the forecaster only offering alerts one day in advance, no information is available yet for Thursday. 

Yellow warnings ask people to remain vigilant over weather conditions but not to take any specific action. 

The forecaster will likely raise these to tier-three ‘orange’ warnings, asking people to remain inside where possible, prepare their home for storms by keeping vehicles parked securely and outdoor furniture tied down, and drive sensibly by avoiding potentially flooded roads.

Residents in the south of France should keep up to date with local weather reports, as well as advice from Météo France, across the period.