Since the weather is so mild in most of California, except at higher elevations, gardeners don't "bed down" their roses for the Winter as might happen elsewhere. That said, our roses still require a yearly pruning to remain productive and healthy. This job is already on my to-do list, but I often end up doing it on a whim when I have the energy and time.
I have about 50 roses, but the process only take a few hours, at most. It usually fills all my garden bins, as the rose canes tend to knit together and not pack as tightly as other materials.
Whatever the weather, be sure to wear long sleeves and long pants made of tough fabric. I have created long gashes in my arms and my clothing while pruning.