Every person who reads a poem has their own take on it. Poems are highly personal and subjective in their reach, but to me this poem speaks very strongly of silence. There is a particular sort of silence that falls after the first heavy snowfall where traffic stops momentarily while everyone adapts, and for a time everything is muffled. There is too much in this poem for just one question but images and sound (or lack of it) feature heavily. In that sense, this poem is like Frost's 'snowy evening' poem. For example, the words :
Every branch big with it,
Bent every twig with it;
Every fork like a white web-foot;
Every street and pavement mute:
make sense because we have just read the title so we know 'it' means 'snow.' In every line we have these casual figures of speech and images - branches 'big' or 'bent' with snow, duck's feet where snow has filled the gaps in the twig forks, the personified hard landscaping feature of 'mute' pavement (sidewalk.) Then there is more personification with flakes that have 'lost' their way, and more street architecture transformed, palings (rails) which seem 'glued' together. The picture is one of minute observation second by second as the scene becomes quieter and quieter towards the end. There are very many more features to discuss within this beautiful serene and silent poem.