Hi Indy:
When you weigh in at night, the result is generally a few pounds more than if you were to weigh in the morning. It doesn't matter when you do it, it is just best to keep it consistent, with the same clothes, robe or lack of each time you weigh in. I chose to weigh in just before my shower, with just my undies on. That way it is probably the lowest. And I wanna be LOW!!!