Changes to daylight hours, temperature and weather will bring about a number of challenges for Ukrainian and Russian troops, the Ministry of Defence (MOD) has said.
In an update on Twitter, the MOD said "any decisions that the Russian General Staff make will be in part informed by the onset of winter".
"Daylight will reduce to fewer than 9 hours a day, compared to 15-16 in the height of summer. This results in fewer offensives and more static defensive frontlines," the update said.
"Night vision capability is a precious commodity, further exacerbating the unwillingness to fight at night.
"The average high temperature will drop from 13 degrees Celsius through September to November, to zero through December to February.
"Forces lacking in winter weather clothing and accommodation are highly likely to suffer from non-freezing cold injuries."
Watch: Russia suffers 'biggest setback' of war in Ukraine.
The MOD also said the "window in which to save a critically wounded soldier is reduced by approximately half", greatly increasing the risk of contact with the enemy.
"The weather itself is likely to see an increase in rainfall, wind speed and snowfall," the MOD tweeted.
"Each of these will provide additional challenges to the already low morale of Russian forces, but also present problems for kit maintenance.
"Basic drills such as weapon cleaning must be adjusted to the conditions and the risk of weapon malfunctions increase."
It comes after Moscow said it had finished pulling its troops out Kherson, with the UK’s Military chief stating Russia has failed and is failing "dramatically".
Chief of the Defence Staff Admiral Sir Tony Radakin said the world is seeing a "continued failure from Russia", which was seen "at the outset".
"Russia wanted to take the cities, it failed. Russia wanted to subjugate Ukraine, it's failed, and it's failing dramatically," he said.