The poem, as a whole, is about loss. It is about how nature reflects our human emotions. In the first stanza, it talks about death and how death can come unexpectedly. Death can come "silent, and soft, and slow," just like how snow falls. He compares death to the way snow can fall. In the second stanza, it talks about grief and denial. It talks about how a "troubled sky" reveals grief. In the third stanza, it talks about how nature reveals what it is like to cope with death and grief.
In the first stanza, "her garments shaken," "woodlands brown and bare," " harvest-fields forsaken," would be visual imagery. "Silent, and soft, and slow," would be an example of auditory, tactile, kinesthetic, and visual. "Descends the snow." would be an example of visual, kinesthetic. In the second stanza, "troubled sky reveals," would be personification because the sky can't be troubled. In the third stanza, "Slowly in silent syllables recorded;" would be an example of kinesthetic and auditory.