Conditions will become wintry. The weather will change markedly from Monday November 18 and is accompanied by a sudden drop in temperatures which could sometimes be worthy of mid-January, according to Météo France forecasts.
A descent of polar air will therefore occur from the middle of next week. It will cause maximum temperatures to drop in the northern two-thirds of the country. Only the southernmost third of France will remain apart.
On Wednesday, the maximum temperatures will drop around 5°C compared to the day before. While it will be 8°C to 10°C in the middle of the afternoon on Tuesday, the next day it will only be 2°C to 7°C in the regions affected by this arrival of cold air. In Brittany, the drop would be limited to around 3°C.
Thursday, which should be the coldest day of the week, the thermometer will fall further. It should be between 0 and 5°C in the regions north of an axis going from Nantes to Lyon. This would place the day's highs between 7°C and 9°C below seasonal norms depending on the location. They would then correspond to levels of mid-January, the heart of winter.
On Friday, levels would remain similar, except near the Normandy and Breton coasts where they could start to rise. The increase would be clear in all regions from late Saturday afternoon. On Sunday, compared to Friday, temperatures would have increased to around ten degrees.
If the deviation from the averages would therefore reach almost ten degrees on Thursday in the coldest regions of the country, on the scale of the whole of France the situation would be a little different. The weather channel explains that the national thermal indicator would be between 3°C and 4°C below normal. This indicator takes into account around thirty weather stations spread across the entire metropolitan area. As the southern third of France will maintain seasonal values or almost next week, these regions will raise the overall level of the country.
Finally, technically there will be no question of a cold snap. This meets several criteria and corresponds to much more rigorous cold levels. The national thermal indicator, which is one of the criteria taken into account, should remain around 3°C above the threshold characteristic of such a phenomenon.
