Depending on where you live or when you take your lessons, you may not be accustomed to winter driving and the potential risks and challenges it can pose. Instructors will never force you to drive in weather you may not feel comfortable in, but it is always recommended to understand how driving is impacted when the weather changes. If weather is extreme, drivers will also let you know in advance of it is safe to drive at all, thus cancelling or rebooking your lesson.
Snow, ice, rain and fog create hazards when driving. This can be icy, wet roads with minimal grip, or fog which will significantly hinder your vision distance. As scary as it can be, all it takes is learning how to be safe in order to overcome these obstacles. Your instructor will be by your side guiding you on how to navigate should you come to any difficult situations, but more importantly getting you to be able to determine safety measures when driving in poor conditions.