snow accumulates this week in France, details by region

The cold returns to France this week and snow is expected to fall this Thursday in several regions in the north of the country. In a bulletin published this Wednesday, November 20, Météo-France announced the placement on orange vigilance of 28 departments due to a risk of snowfall and the formation of ice.

The departments concerned are as follows: Côtes d’Armor, Île-et-Villaine, Calvados, Eure, Manche, Orne, Mayenne, Sarthe, Eure-et-Loir, Loir-et-Cher and the Loiret. To these are added those which make up Ile-de-France, but also Aube, Yonne, Haute-Marne, Côte-d’Or, Vosges, Haute-Saône, the Doubs, the Territoire de Belfort and the Haut-Rhin.

According to information from The Weather Channelsnowfall extends this Thursday from inland Brittany to the south of Normandy, towards Maine, Beauce, the Central region, the south of the Paris basin, to slide during the afternoon towards the center east, on the edge of Franche-Comté and southern Alsace. On the Île de France side, nothing is certain, even if a few snowflakes should be seen.

From this Wednesday, a clear cooling of temperatures was felt due to the formation of an air mass close to -35°C at 5000 m altitude according to Keraunosthe observatory for tornadoes and violent thunderstorms. This degradation is due to a new oceanic disturbance, leading to the collision of soft, humic air with the cold air already in place.

The Weather Channel explains that a very hollow depression named Caetano arrives in the morning this Thursday over Brittany and crosses France from west to east. The institute even gives details by region: “The depression is associated with a significant conflict between mild Atlantic air and much colder air present in the north of France. In contact with these two masses of air, precipitation is intense and occurs in the form of snow from northern Brittany and Normandy to Burgundy-Franche-Comté, via Center-Val de Loire, Ile-de-France and the south of the Grand Est region”, explains the specialized media.

And the snow therefore appears, it is a white coat which forms over a large territory: “Due to the intensity of the precipitation and the temperatures between 0 and 2°C, the snow easily sticks to the ground on the plains and plateaus from 150 m altitude with 3 to 8 cm and locally 10 cm above 300 meters The hold is more difficult in valleys and highly urbanized areas with 1 to 3 cm. This snow will often be accompanied by gusts of wind. and traffic conditions could be difficult, particularly on the secondary network,” indicates La Chaîne Météo.

Despite everything, the situation remains complex to predict for the end of the week: even if the numerical models were able to anticipate the risk of a “rain-snow” episode for the day of Thursday, it is difficult to determine the precise trajectory of this depression straight from the Atlantic. This is why the numerical models cannot state with certainty that snowflakes will fall in the regions located at the extreme of this phenomenon, which is the case for Île-de-France.