This question was looked at very recently on GoY. The general view was that it is not a good idea to lay turf in winter. Best to leave it until the grass is growing again in spring. Googling shows some turf laying companies say it is OK to lay when there's no frost in the ground.They may be saying this so they can sell turf!

I've just laid 140m of it, fnished just a day before all that rain. Probably ok 'til C*******s, as we don't usually get hard frost before Jan. However, if you're in a frost prone area, or up North, I'd wait 'til March, but prepare the gound now, and let it settle. Prior to laying the turf in spring, all you'll need to do will be level out the hollows, tickle the surface so there's a fine tilth for the grass to root easily into, and away you go. Phil

Where in the country are you Phil?