The rains spared no region in this first decade of October. They were very copious in certain regions of the north and east so that for certain cities such as Nantes, Paris or Besançon, the rainfall totals far exceed those observed over the entire month of october. These very heavy rains were the cause of numerous floods and floods.
After a few days of calm and dry weather during the first days of October, two very active disturbances affected France from October 7 to 9. The first circulated in the east and south-east with up to three weeks of rain in the Lyon region. The second concerned an axis going from the Pays de la Loire to the Ardennes via the Paris Basin, regions less accustomed to heavy autumn rains.
A very wet first decade of October © The Weather Channel
The map above highlights the high rainfall in the eastern regions with cumulative rainfall exceeding 100 millimeters in 10 days in Franche-Comté, eastern Burgundy as well as part of the region Rhône-Alpes. These regions had already been very wet in September so that the soils were saturated with certain plots transforming into real lakes. We also find the axis of lasting rain from October 9 with the equivalent of a month of rain in 24 hours from Pays de la Loire to the Ardennes via Ile-de-France. The rainfall over the first decade of October is close to 90 mm in Paris and sometimes exceeds the 100 mm mark in the Pays de la Loire. For example, 111 mm fell in Nantes, including 83 mm in 24 hours. Following these rains which saturated the soil, numerous floods and floods occurred with a red level alert issued by Vigicrues for Grand-Morin in Seine-et-Marne and for Loir in Eure-et-Loir.
Very wet first decade of October © The Weather Channel
The prize for rainfall goes to the city of Besançon with 154 millimeters while the average monthly rainfall is 111 millimeters. The capital has already recorded the equivalent of nearly a month and a half of rain while October is far from over. Note that in Paris, the rainfall since the start of 2024 has already exceeded the average annual rainfall.
If a lull is expected for the next 3 days in terms of precipitation, a further sharp deterioration in the weather is expected for the middle of next week.
