It is. Sorta.
The way it is currently set up is you enter a start time and date and an end time of date and a fixed interval between frames, and it simply takes a picture every x minutes or x seconds between the two dates.
There is a Wishlist item to vote on to give you what you ask for, but in the Wishlist item they show a workaround, if you can do without the camera at night: Schedule the turning on and off of the camera using a rule. For instance, have it on only from sunrise to sunset, or within an hour of those times. When the camera is off, it will not record the timelapse. When it is on it will start up again. 