Autumn in Colindale Park

How do you describe it when the trees 
are full of so much colour that they throw
their leaves to earth, as if they somehow know
the lingering winter stillness held in snow
is creeping through the air by slow degrees?
How do you define this autumn shift
of light, the coming moisture in the air
that speaks of rain, as if it had to bear
the weight of sorrow held in harness there,
knowing this sadness is a yearly gift?
Descriptions, definitions fail to catch
the yearning autumn brings to all who sing 
the song of seasons turning, tuned to match 
the love of winter, the returning of the spring.