Weather News: Next week: severe weather with strong winds, heavy rain and snow – METEO CONSULT – 15-DAY WEATHER FORECAST
Weather conditions are expected to be very changeable and disruptive early next week with a very dynamic low pressure northwesterly flow making active disturbances. Starting Sunday, an orange level weather warning will be in effect for several weather parameters: strong winds, heavy rain and risk of flooding, snow.
Why does weather pose a threat of severe weather?
A large low pressure system will affect Western Europe early next week. A strong upper-level jet stream will deepen sharply and fuel heavy rain, strong winds, and high activity troughs with snow in the mountains. The exact trajectory of these depressions remains to be determined, but the latest atmospheric models show that the southern part of the country will be at the forefront of bad weather with heavy rain in the south-west, heavy snow in all terrains and strong winds. Atlantic and Mediterranean coasts. In the context of such weather, our services will be on special release for several days and will be running between Monday and Wednesday for this episode of bad weather.
Heavy rains in the southwest
The most active disturbances in this very dynamic northwesterly flow will be in the southwestern part of the country with showers in the first half of the week. As is often the case with this type of sea flow, the accumulation of rain in the foothills of the Pyrenees will be most important, blocking it. Between 100 and 140 mm of rain is expected over 3 days in the Basque Country and the foothills of the Pyrenees, which is about a month’s worth of rain. There is a possibility of flooding and flooding in the waterways of the Adur Garon basin. From a general perspective, total rainfall expected across the great southwest will average 50-60mm between Monday and Wednesday, equivalent to 15 days of rain. These will be very beneficial rains in certain sectors, such as Midi-Toulousain, where the lack of rain has been significant for several months. It should be noted that rainfall accumulation will be less important in the Roussillon plain, where the expected few rains will not be enough to stop the severe drought in this region.
Heavy snow fell on our mountains
With the arrival of maritime polar air over France, the air mass will be cold and wet enough to bring snow to any elevation in the mountains. With a disturbed regime from the west to the northwest, the snow cover will fill all our massifs. The greatest amount of snow will be in the Pyrenees, the Massif Central and the Alps, although it is still difficult to determine the amount of snow. However, we can predict some average snow accumulation ranges for the first part of the week: 60-90cm in the Pyrenees at 2000m, 40-50cm in the Massif Central at 1400m, 30-60cm in the Alps. At 1800 m, 15-30 cm in Vosges and Jura, at 1200 m. At times, blizzard conditions can be observed in open mountain ranges and plateaus with strong winds. Also, beware of the risk of snowfall, which can cause problems on mountain roads. Access to stations at certain altitudes may be temporarily difficult.
It can be cold and snowy down to the plains
The drop in temperatures that will begin on Sunday will gradually increase next week with the installation of a north-northwest current, which is increasingly provided with cold air. Therefore, we will initially find the seasonal temperature between Sunday and Monday. Our national thermal index (the average of forecast temperatures for 30 cities in France) shows below-normal temperatures for the season from Tuesday, with a possible worsening of the cold under the influence of calmer and drier weather later in the week. conditions. It should be noted that in the last ten days of December and the first ten days of January in France, you have to go back to December 18th to find below-normal temperatures for the season marked by record mildness.
As for the risk of snow in the plains, given the level of temperatures, some plains regions may be affected by snow, especially between Tuesday and Thursday.
We’ll see a risk of snow on the plains in the central regions on Tuesday, which will sweep across much of the southern half of the country. The south of the Centre-Val de Loire and Bourgogne-Franche-Comté regions and Auvergne-Rhône-Alps are the regions most exposed to lowland snow according to our latest forecast models. It is too early to determine the expected amount of snow. Snow may also fall in the form of sleet near the English Channel and in the northeast. Reliability becomes more limited on Wednesday, but the risk of snow on the Plains may continue from northwest to central.
A strong wind will blow in the west and south
If the strong wind on Monday can disturb many regions under the influence of the depression in the North Sea, and especially our coasts, special monitoring of the situation is required, especially on Tuesday. The depression, which can be described as a low-pressure bomb, will expand rapidly near the Atlantic Ocean under the influence of the strong Jet Stream (a strong current at high altitude). Its exact trajectory is still somewhat uncertain, but it should reach the Atlantic coast late Monday into Tuesday night. It is expected that the strongest wind will blow in the south of the trough. At present, the coasts of Aquitaine and Charente are most exposed to stormy winds (100-120 km/h). Strong winds of 80-100 km/h are possible on Tuesday morning in southwestern areas. Strong winds will eventually reach the Mediterranean, with strong west-northwesterly winds expected between Tuesday afternoon and next night. Winds are likely to exceed 100 km/h on the most exposed coasts, with a risk of 130-140 km/h at the tip of Corsica.
After a very unsettled first part of the week with bad weather, the weather should calm down considerably in the second part of the week as the depressions subside. With calm and dry weather, cold will increase with frequent and sometimes severe frosts, especially on snow-covered lands.