Day to Night- from the Window

With stealth the darkness creeps
And seals the day
With hardly a difference of 
Day from night;
Ink black rooks
From their roost 
Take flight,
Circle, then return to the
Same bare branches
Silhouetted against
The soot grey sky;
Wintery sleet
Falls;
The cold seeps
Through every gap;
Even the log fire
Struggles in the grate; 
There is no wind 
Just empty blackness.