The Russians have been preparing to attack, it is clear, by moving troops and equipment in to reinforce and prepare their local hand puppets.
And a winter offensive makes sense as an effort to keep the coming renewal of the war limited to eastern Ukraine's Donbas region.
That is, if Russia attacks overtly during the winter months, both Ukraine and NATO Europe which rely on Russian energy to stay warm will find that they cannot oppose the attack too strongly or broadly lest they risk freezing should the Russians cut off energy exports to and through Ukraine.
On the other hand, if that is the plan it may mean that Russia is truly seeking a limited victory in the Donbas rather than a more expansive offensive to create a land bridge on the north shore of the Sea of Azov down to Crimea.
UPDATE: An additional source of energy uncertainty:
Ukraine gets some 40 percent of its power from coal-fired plants, and has traditionally had a surplus of coal, producing some 86 million tonnes at last count in 2012.
But the Russian-backed rebellion in the east has cut the government off from large swathes of the coal-rich mining region of Donbass.
Then, without warning, Russia announced it was stopping coal supplies to Ukraine last week, claiming "force majeure" but offering no explanation.
I'm sure if Ukraine offers just token resistance to the coming Russian offensive, the coal will flow again.
Russia has sent more "aid" to eastern Ukraine, no doubt to prepare for the attack:
Ukraine said on Sunday that a convoy of 106 vehicles had entered its eastern territory from Russia without Kiev's permission and accused Moscow of once again using humanitarian aid shipments to send weapons and ammunition to separatist rebels.
This could get ugly and cold before it is over.
UPDATE: I'm sure this unfortunate event is a coincidence:
Ukrainian Prime Minister Arseny Yatseniuk said on Wednesday an accident had occurred at the Zaporizhye nuclear power plant (NPP) in south-east Ukraine and called on the energy minister to hold a news conference.
Bad things seem to happen to weak people who oppose Putin.