In just a few days, this beginning of spring 2022 should be marked by a drop in temperatures. Why are we going to lose up to fifteen degrees in places in France, this week of March 28?
Spring is here. The meteorological atmosphere at the end of March 2022 does not allow us to doubt it. The maximum temperature exceeded the 20°C mark in France on March 27, reaching 24°C in some places.
” It was the first day of the year with an aggregate maximum temperature indicator above 20°C, 13 days ahead of the median for the past 75 years. », commented Gaétan Heymes, forecasting engineer and snow scientist at Météo France, on Twitter. But don’t put away your coat and gloves at the back of the closet right away: the cold is coming back.
” The mercury will drop drastically from mid-week. We can lose about fifteen degrees between Monday and Friday in places “, warns Météo France in a press release published on March 28. In a tweetthe service states that “ in just 4 days, the maximum temperatures will drop by an average of 12°C, dropping from an average of 21°C in France on March 28 (worthy of the end of May) to 9°C on April 1 (worthy of a mid February) “.
Is the cold in early spring so surprising?
This episode of cold is not so surprising. Météo France even judges this classic rhythm during a season like spring. The changes are frequent and announce sort of summer with a gradually warming air mass “. On Twitter, Météo France forecasting engineer Alexandre Flouttard confirmed that spring is a season of contrasts “.
The meteorological service also points out that this kind of episode has already happened, especially in 2021. ” Many monthly heat records were broken at the end of March 2021 and unprecedented cold values were recorded in early April 2021. »
Nevertheless, the episode scheduled for 2022 for the end of March and the beginning of April should be less intense than that of last year, even if frosts and snowfall at low altitude are not excluded in France.
How to explain the cold?
The drop in temperatures is explained by meridian flows (parallel to a meridian, an imaginary line passing through the Earth’s poles), favoring the trajectories of air masses on a north-south axis, which can contribute to sudden variations in temperatures. Thus, in 2008, we could have had 3 centimeters of snow in Paris on the night of April 6 to 7.
This end of March is ” the arrival of an upper cold block from the Arctic which is the cause of the drop in temperature, precise Gaetan Heymes. Alexandre Flouttard uses the term thalweg, that is to say a barometric trough, an area where the atmospheric pressure is lower than the surroundings. This trough, associated with the cold air, is moving towards France and part of Europe.
How will the cold come to France?
Concretely, how will the cold settle in France this week? This will be gradual, indicates Météo France, and begins this Tuesday, March 29, 2022 with the arrival of a first disturbance. ” Its numerous clouds as well as its rains will first allow the minimums to increase but the maximums will begin their chut, ”says the establishment. Despite this disturbance, temperatures should still remain quite high for the end of March.
It is after the passage of this disturbance that the arrival of polar air is expected on Wednesday, March 30, from the northwest. ” The minimums will still be far from the frosts but the mildness of the maximums ends with values closer to seasonal normals “, completes Météo France. Thursday, April 31, the mass of cold air should settle in and temperatures will continue to drop. ” During the night from Thursday to Friday, sleet as well as snowfall in the plains are possible on the coastal departments of the Channel. All this remains to be clarified. “, adds the meteorological service.
This sequence of events makes possible the arrival of frosts on Friday April 1 in the morning, in the northern half, then as far as the south-west during the weekend of April 2 and 3.