Sentence:  Thus in a context in which there has been discussion of snow but <WSD>mention</WSD> of local conditions is new , dominant stress will probably be on here in it rarely snows here , but in a context in which there has been discussion of local weather but no mention of snow , dominant stress will probably be on snows . 
Meaning of the word marked with <WSD> tags:  a remark that calls attention to something or someone