Remember this: concrete curing is NOT an evaporative process - ie. the
concrete does not really need to "dry" in order to cure. In fact, it's
better for the end strength of the pour if it is kept moist during the
cure process. There is a chemical reaction that combines the water
with the portland cement in the concrete mix. The cold weather will
probably slow down this reaction, but the moisture will actually help
it in the long run and won't slow the cure down any.