Could there be heatwaves in winter?
Define 'heatwave'. We here in Western New York would call that a January thaw. Sometimes it gets up to 50. But that's just for a day or so.
Yes, a few years ago it would in the 60's and 70's in New York and Boston around Christmas.
Depends on where you live. I'd kill for one here in freezing cold Charlotte.
Yes, there can be. We've already had at leat 2 so far