。
I hear this has been an unusually cold winter.
Literal
Unusually cold winter [copula-だそうですね].
~そうです is the hearsay form — 'I hear that, they say that.' Attached to a plain-form predicate, it reports secondhand information. 例年になく ('unlike usual years, unusually') is a set adverbial meaning something is out of the normal range. ね softens into agreement-seeking.