After a very dry start to the year 2022, the rain will finally fall this weekend in the Hérault as in all of the south-east of France. Precipitation that put an end to a long period of winter drought.
After more than forty days without a single drop of rain, the first rainfall should appear on Saturday morning in the east of the Hérault department. According to Météo France, scattered rains are expected in Montpellier, Lunel and Saint-Mathieu-de-Trviers. In the afternoon, the rain reached Béziers and Bédarieux, then the whole department in the evening. 1 millimeter of cumulative precipitation is expected.
Precipitation which will intensify overnight and throughout the day on Sunday with a total of 3 millimeters. From Monday morning, sunny spells will again be predominant.
The return of rain this weekend puts an end to a long period of winter drought. Indeed, many stations around the Mediterranean have not experienced daily precipitation of at least 1 mm since the beginning of the year. This is particularly the case for Montpellier, Nîmes, Aigues-Mortes and Sète.
Indeed, since the beginning of the meteorological winter, on December 1, France has been experiencing an anticyclonic meteorological configuration which pushes precipitation towards the north and east of Europe. Long periods without rain follow one another, interspersed with a few brief rainy disturbances.
According to Météo France, the phenomenon is not uncommon. “We therefore realize that the current durations of meteorological drought are not exceptional. They generally have a return period of around 10 years. But if the current period of meteorological drought in the Southeast still lasted the next few weeks, we would then arrive at an exceptional situation”explains an expert.
Winter droughts have a direct effect on underground water reserves. Because usually, it is in winter, from December 1 to March 1, that precipitation is said to be “effective”: these large quantities of rain penetrate deep into the ground and then feed the water tables.
For the moment, we observe a deficit of 40% of rain compared to the normal. But there are still 2 months left for the so-called recharge season.
Meteo France
However, since the beginning of December, the south-eastern quarter of France has experienced a significant rainfall deficit. In this context, groundwater recharge could not take place. The emptying of the water tables, that is to say the drop in their level, could begin at the beginning of spring with the rise in temperatures. A worrying scenario, but Météo France is not yet sounding the alarm: “For now, we are seeing a 40% deficit of rain compared to normal. But there are still 2 months left for the so-called recharge season.”
Precipitation is therefore necessary so as not to repeat the scenario of spring 2021, where the drought had started in mid-April. Due to an abnormally low level of groundwater in the Hérault, the prefecture had indeed placed the entire department on “vigilance” in the face of the risk of drought, the last stage before the implementation of restrictions.
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