Yep, I'd have no problem hearing that.Can I use these words in this way?
"Last year we experienced a cold snap/ a cold spell; it was the first time I experienced -30 degrees."
Jimbo is correct in these definitions, and either of the options in your example is acceptable, so apply the one that most closely fits his guide.Both work but they mean slightly different things.
"A cold snap", to me, is a sudden drop in temperature overnight that is either unexpected or unseasonable. "A cold spell" could be a prolonged period of cold weather but it may not come on suddenly and it may not be unseasonable.