Cooling has been confirmed since Thursday in northern France. This sudden drop in temperature will be accompanied by a snowy episode between Upper France and the Paris Basin. Reliability is becoming more and more evident despite the still uncertainties regarding soil resistance and planned thickness. Here are the regions that will be most affected by snowfall this weekend.
Update for Wednesday, March 30th.
The numerical models used to develop these forecasts are starting to match the expected development of the weather on Thursday and Friday. Snow has been confirmed since Thursday morning on the Hauts-de-France plateau with a low risk of ground resistance. Then the rain-snow disturbance will continue on Thursday evening to the south and touch the Ile de France on the night of Thursday to Friday. Snow could then fall all night on these two areas, also descending towards the Center. If this area is the most vulnerable, there is still uncertainty about border sectors such as Champagne-Ardenne on one side and Beaus on the other, where snow may also fall, but in small amounts. The depth of snow on the ground is usually estimated to be between 1 and 6 cm depending on the sector, holding more on plateaus and with difficulty in large valleys and in the urban sector. For example, the snow will probably not survive in the inner suburbs of Paris… an evolution that nevertheless needs to be confirmed in our next updates.
Arrival #snow remains relevant from tomorrow morning in Hauts-de-France. Especially on the night of Thursday to Friday, he descended into the Ile-de-France and the central regions. This zoning is becoming more reliable, but will still require adjustments❄️ pic.twitter.com/rpMnfhKaNA
— Weather channel (@lachainemeteo) March 30, 2022
The article was written on Tuesday, March 29th.
Difficult weather conditions
If the weather scenario proposed below describes the one that seems to us the most probable today, then it should be borne in mind that the weather changes that contribute to snowfall on the plains are complex due to the always possible displacement of depressions and disturbances that cause the evolution of weather and temperature levels . Within two degrees, the snow sticks to the ground or melts. As for the upcoming episode, doubts still remain. Thus, some of the numerical models used to develop forecasts include a snow episode that would be visible over the Paris Basin, while others do not. Therefore, we must keep a close eye on our next updates.
The arrival of snow from the north on Thursday morning
The weather in France will begin to change drastically from Thursday morning north of the Loire when a cold northeasterly wind blows straight out of Scandinavia. Cooling will be fast. In this context, sleet could begin as early as Thursday morning north of the Seine. It is even possible that these first snows of this episode will temporarily linger on the ground in the Picardy plateau and Boulogne hills before melting during the day when temperatures are still positive.
Snow expected in Ile de France Thursday evening and night
On Thursday, when temperatures do not exceed 5°-6°C north of the Seine, there will be rain mixed with snow before moving towards the Paris Basin. They could reach island of france in the late afternoon in the north of the region. Then, as temperatures drop from Thursday night to Friday, snowflakes could replace rain between the Oise, Paris and Orléans. In the capital, the snow would have melted without holding onto the ground, but it is possible that the plateaus turn white overnight, especially towards the Center district. Several centimeters are already provided, but today it is difficult to indicate how much the quantities provided by the models diverge. In these regions, the snow will stop overnight, but may continue until the morning, when then the landscapes may turn white.
Increased risk of snowfall in central regions
This episode could be more noticeable in the central regions on the night of Thursday to Friday. Snow can replace rain between the Central Region and Limousin, from the plains, but even more so at an altitude of 300 to 400 m (foothills of Limousin and Auvergne) with a snowy landscape on Friday morning. A few inches of snow is likely to cover the landscape on Friday morning in a very cold atmosphere with a northerly wind. There is a possibility that the snow will move further east and also fall between the Loire, Lyon and Burgundy on Friday morning.
White Friday morning between Limousin and Central East.
These regions should not escape the snow on Friday morning with the advance of cold air into the south of France. Cold and snowy weather will then spread from the Midi-Pyrenees region south of the Massif Central and the Alps, passing through the middle Rhone valley and Lyon. Snow can stick to the ground at an altitude of 400 to 500 m, which can change driving conditions, especially on the plateau (Lozère, Haute-Loire, Aveyron, Cantal) and also in the Alpine departments. The lower mountain will then experience a notable winter episode, which was rare this winter. As such, it may snow until Saturday morning between Auvergne east and the Alps, with the exception of the southern Alps, which will be subject to strong northerly winds. Snow during this period will also fall in the Pyrenees, also from a height of 400 m, which is very little, especially for the season.
Finally, we recall that the reliability of this evolution has yet to be confirmed in the regions described above. So much the onset of a cold is being acquired as the regions that will be covered in snow have yet to be clarified. However, reliability is higher if snow falls between the Limousin, Massif Central and the Alps, while in border areas such as the Paris Basin there is uncertainty about the occurrence of these snowfalls. On the other hand, even if snow appears on these flat areas, it would be premature to indicate its thickness on the ground today.