long winter -uzun kış or is kış uzun better?

lots of snow today - bugün çok kar var

It has been a long winter - ?

I understood snow storm is kar fırtınası. But any idea when I use possessive in these cases? I just wouldn´t have thought that the snow is owned by the storm.

long winter -uzun kış or is kış uzun better?

lots of snow today - bugün çok kar var  ---> Correct !

It has been a long winter - ?   Uzun bir kıştı.

 * These  type of noun clauses are bit different, I mean regard them as the first noun is describing the second noun ,  informing us about what is the second noun used for or what is it for.

 snow storm ---> kar fırtınası

Here , snow is describing the type of the storm rather than possessed by the storm.

El + araba + sı ---> El arabası.  Literally "hand car" ,  it means " wheelbarrow".

Because that particular trolley is used by HAND, we name it  as "The car that is operated by hand"

So, this is giving us the description of  how it is operated rather than how two things possessed to eachother.

Fabrika atığı --> factory waste

[Fabrika atık + ı ]

In this noun compound , the category of the waste, the type of the waste it says.