Between Saturday and next Sunday, polar air will plunge from Scandinavia towards the Mediterranean basin, bringing with it a gale followed by a general cooling.
Risk of gale in the north Saturday and Sunday in the south
After an already very rough and windy Saturday with a risk of gusts of 100 km/h in the north of France, temperatures will drop on Sunday. On Sunday, the Mediterranean regions could be affected by stormy gusts of mistral and tramontane, when polar air arrives at sea.
© gmatricon
Temperatures drop on Sunday
It is especially during the week of the 8th to the 13th that the cold will be the most severe. Next Sunday, maximum temperatures are expected to not exceed 4 to 7°C in 3/4 of the country. We would be 2°C below normal. We are not talking about a cold snap at this stage, but what is certain is that a cold period is expected thereafter since temperatures should remain 2 to 3°C below normal throughout the week from the 8th to December 13.
Cold weather episode from December 8 © the weather channel
Towards a freezing feeling because of the wind
The mistral, the tramontane for the Mediterranean regions, the burle for the Massif Central and the north wind for the north of the country will be there from next Sunday. These sometimes strong winds will accentuate the feeling of cold. The feeling may even seem icy in the wind!
Will this cold be intense, will it last?
All models envisage a cold period from December 8 to 13. Our national thermal indicator indicates that this cold, without being exceptional, should last several days. It is especially the eastern regions which should be most impacted by this cold.
Frosts will return to almost the entire country during this period. They could locally be severe.
National heat indicator © the weather channel
Is snow possible on the plains?
What is certain is that all mountain ranges will benefit from snowfall, from the Vosges to the Jura, the Alps, the Massif Central and the Pyrenees. The quantities could be significant, particularly in the Pyrenees by orographic blocking effect and from the Jura to the Alps by return from the East. In the plains, the situation is not reliable, everything will depend on the origin of this cold air, whether it is maritime polar, in which case this risk exists, or continental and dry. At this stage, it seems that the eastern, northern and central plain regions are the most exposed to this risk, although this zoning may vary widely.
risk of snow Sunday 8 and Monday 9 December © the weather channel
Uncertainties about the origin of the cold: maritime polar or dry continental?
If the cold is acquired, the mass of air which will cause it is not made reliable. If it is a dry continental cold, a risk of severe frosts and temperatures which remain negative in the east of the country in the afternoons is entirely possible. If it is a more maritime polar air, the consequence would be less cold weather, but potentially snowy, up to the plains. Finally, it is also possible that this cold snap is only temporary and that the ocean flow quickly picks up again, but this scenario is very much in the minority among all the weather models this Sunday.
We will keep you informed daily of the evolution of this cold period to refine our forecasts.
