Update: The Dynamic Weather patch is now live for DriveClub.
As you can see from the screen captured by PlayStation's Envisager, below. The patch adds weather to every track, adds two new tracks for both Norway and Canada and adds support for the new Redline Car Pack and Redline Tour Pack, the latter of which adds 11 new events, 5 new trophies and more.
Original: DriveClub is to get it's Dynamic Weather update tomorrow.
Here's the post confirming the news, along with a video.