A cold snap is confirmed from this Thursday in northern France. This sudden drop in temperature will be accompanied by a snowy episode between Upper France and the Paris Basin before affecting the Massif Central and eastern regions. Here is an update on the progress of this snowy episode that will affect many regions.
As we announced a few days ago, winter is back this weekend. The first showers came this morning between the Nord-Pas-de-Calais and the hills of Normandy. At a temperature of 2-3°C, these first seen snowflakes had no consequences. They indicate a clear cooling of the air mass when the wind direction is in the northern sector.
The beginning of the snow episode at the end of the evening in Nord-Pas-de-Calais.
This evening the disturbance will come from the North Sea and the Benelux in the area of Nord-Pas de Calais. At first, rain or sleet is expected mixed with temperatures between 2 and 4°C. After 22:00, with increased intensity of precipitation and an increase in the north wind, the temperature will drop, and the rain will gradually change to snow. In the middle of the night the floors will turn white. Please note that there should be more snow in the Pas de Calais than in the Nord department. At dawn, we expect 1 to 3 cm, in some places 5 cm in the north, knowing that snow will often be difficult to keep in the center of urban agglomerations. In the Pas de Calais we expect an average of 2 to 5 cm, in places 10 cm in the heights and hills of Artois and Boulogne. It should be noted that the northerly wind, which will blow with strong gusts, will create very poor road conditions and reduce visibility. Snow behavior on the Opal Coast will be more random, depending on the exact temperature level (between 0 and 2 degrees).
Snow will fall on Picardy after midnight. The Somme and Oise will be particularly affected by snowfall, which will continue throughout the day on Friday, even if the snowfall becomes lighter and intermittent. Snow will be accompanied by strong gusts of wind up to 80 km/h. Snow can easily stick to the ground in the plains. We expect an average of 1 to 3 cm in Aisne (indefinite delay in the city), 2 to 5 cm in the Oise and the Somme, and in some places 7-8 cm in the hills of the Pays de Bres.
The arrival of the snow at the end of the night in the Île-de-France and Upper Normandy
Starting in the first half of the night in Hauts-de-France, the snow fell around 3-4 am in Upper Normandy and at 4-5 am in the north of Ile-de-France. The greatest intensity will be observed in the late night and early morning over Normandy and west of Ile-de-France. In the suburbs of Paris and on the Seine and Marne, less intense snow will fall, and the snow will be difficult to keep on the ground, especially in the city and on wet roads. We expect 1 to 3 cm, in places 5 cm on the Yvelines and Val d’Oise. Snowfall will become lighter and more intermittent from the late morning and afternoon. At temperatures close to 2°C, there will be no grip on the ground, and the snow that fell in the late night and early morning in the west of the Île-de-France region will gradually melt. Watch out for a northerly wind that will gust at 60 km/h, creating a feeling of chill (around -2/-3 in the morning).
Friday under the snow in the central regions and on the reliefs of the east
The disturbance will arrive Friday morning in Center-Val-de-Loire with light to moderate snowfall. Bos is the most susceptible to snowfall, expected from 1 to 5 cm. In the rest of the area it will be a simple pollination with slight discoloration without the effects of plains and plateaus. Snow usually does not create traffic problems as the temperature is not cold enough.
On the other hand, weather conditions are expected to be more challenging in Limousin and Auvergne with more consistent and extended snowfalls during the day this Friday at 300-400 meters above sea level. We expect 2 to 6 cm on the first hills at 400 m and 6 to 10 cm above 600 meters. On the open plateaus, the burle (north wind) will blow strongly.
It will also snow most of the day on the eastern terrains, in particular the Jura and the Northern Alps at very low altitudes.
Saturday: snow on the plain in the center-east, ice in the north.
Snow disturbances will affect regions stretching from the Massif Central to the eastern borders with snow to the morning plain in Burgundy-Franche-Comte and Auvergne-Rhone-Alpes. The snow will hardly stay on the plain, but will give way to the ground a few centimeters from the first hills (300-400 m).
North of the Seine, if the weather turns dry again, beware of icy roads due to slightly sub-zero temperatures (0 to -1°C) at dawn. Frosts could intensify and reach many regions on Sunday and Monday morning with the risk of damage to fruit trees.
Finally, this event is notable because it occurs late and follows a mild winter marked by the absence of snow on the plains. However, this is not exceptional, since similar events have already occurred in the past in early April.