While 2018 is already among the three warmest years since 1900, and that the month of October has been remarkable, so far, by its mildness, even its summer temperatures, the winter will launch a brutal offensive this week -end. No region will be spared. In addition to the north-north-east wind and the rain, the cold will drop the thermometers to December values. Explanations.

Forget about the Indian summer and the sometimes summery sweetness that prevailed so far in October: here come the cold, the true, the winter temperatures - and, incidentally, the wind and the rain. We will almost go from summer to winter without going through the autumn box.

In question: a descent of polar air on our country. In other words, a mass of polar maritime air, currently located near the Arctic, not far from Spitsbergen, will debut Friday on the north of France. Before moving south south Saturday and settle for a few days.

Cold stroke this weekend / invasion of a mass of maritime polar air on France: the air that will be Sunday 28/10 in the evening on #CountryBasque is currently located in the # Arctic, not far from Svalbard.

retro-trajectory NOAA HYSPLIT based on the GFS run of this 23/10 12UTC pic.twitter.com/3XF45Ufr77

- Etienne Kapikian (@EKMeteo) October 23, 2018

Forecast || First winter offensive: The month of October has been remarkably mild so far, but temperatures will drop this weekend. https://t.co/GNgHsRYiX1 pic.twitter.com/HWMlu5oW3o

- Météo-France (@meteofrance) October 23, 2018

Translate: the wind will blow from the north and plummet all schuss at home from the high icy latitudes. Because the anticyclone is there. Often synonymous with good weather, this phenomenon of high pressures will sadly position quite north. Look at the map below: the wind, which turns clockwise around an anticyclone in the northern hemisphere, rises to the far north, catches chilly air and descends to the south to deliver this cold all fresh.

A high pressure high located in latitude, a long dorsal and look at this magnificent flow of north which will tumble home from Friday. | WINDY

As the announcement Météo France, "from Friday, a cold air mass of maritime polar origin will flow through the Channel, to win the whole country in the day of Saturday. Temperatures will drop dramatically, with rain and even snow at low altitudes on all Sunday massifs. "

#Neige: she will make her return on Saturday and will fall more and more low Sunday and Monday. More than 30 cm in altitude and probably snow on the ground up to 700 m on all reliefs. Possible Giboulés to the lowlands Monday in the Northeast https://t.co/LurtDG8MeE pic.twitter.com/eabPY2F474

- Agate Weather (@AgateMeteo) October 23, 2018

Do not panic, though: this cold and wet episode at a time should not last. Temperatures are expected to rise somewhat at the end of next week. And consolidate the high averages of the temperatures of this funny autumn.