Motorists in mountainous areas of France have been urged to ensure their vehicles are ready for winter driving as the first cold snap of the season sends temperatures plummeting.
A mass of cold, humid air from the north has descended across the entire country, meaning temperatures are about 2C lower than normal for the time of year - and conditions are set to worsen towards the end of the week.
The cold spell comes exactly one month after France basked in summer-like temperatures.
Over the next few days, minimum temperatures will range from -2 in the north to 7C in the south, and 10C near the Mediterranean" while maximums will hover around 5 to 8C in the east, from 9 to 11C towards the Atlantic and 12 to 13C around the Mediterranean, forecasters said.
"This week, we are passing under the influence of a vast low-pressure system," says Gilles Matricon, meteorologist at La Chaîne météo, with "a cold and humid north wind[which] will bring a lot of rain, wind and snow at medium altitude.
The cold will get worse as the week progresses. From Thursday, "a period of very bad weather will settling in because of the deepening of a very active depression, with heavy rains and sometimes violent winds in the West", forecasters said.
This turbulent weather system will reach the east and southeast on Friday, and could lead to heavy snowfalls at altitudes of 1,000m.
Maximum forecast temperatures for the end of the week are expected to be lower than January.
In some mountain regions, local authorities have issued a reminder that winter driving equipment, such as winter tyres, are now mandatory. The avalanche risk level in Ariège, les Hautes-Pyrénées and Haute-Garonne has been raised to yellow.
Already, many ski resorts have seen snow - though they have said it is too early for many to open. Some Pyrenees resorts have said they plan to open between December 6 and 9, in time for the Christmas holidays.
Météo Pyrénées posted these images from Pic du Midi, taken eight days apart.