The art of landscape photography
Good light is essential in the landscape photography: if the light is poor, there are no possibilities to capture excellent landscape photos. Because landscape photographers use only available light (at least typically), the only way to guarantee good light is to be in the right time in the right place.
So planning is essential part of the landscape photography. You can be extremely lucky, but in the most cases, the best pictures demand planning and persistence. Planning requires that you think what is good weather for particular location and subject. You must also study the location in advance, e.g. find out the directions of sunrise and sunset at different times of year.