Choose colours cobalt blue, raw sienna and neutral tint (or paynes grey which has a little more blue) very small amount of burnt sienna

beware the neutral tint will give a very strong dark colour

 snowjura1    snowjura2    snowjura3
Sketch composition - line of dark trees should not be across the middle

Mix up mid tone of cobalt. Wet paper from the mountain line upwards - paint blue all over then dap out the clouds with kitchen paper.

Dry

  

Add in distant mountains with cobalt + grey, darker for mountains slightly lighter same colour for the lake. Dry

Mix up dark mixture of blue + grey and paint in tops of trees with a rigger then take larger brush and paint down to the snow line

 

  

Paint fence post and shadows in the snow. Use a toothbrush for spary effect
 snowjura final        
Add finishing touches, Scrap out lines in trees with a scalpal (make sure paper is completely dry). Add a few more shadows to underside of clouds