Is Global Warming causing early Bud Break? A lot of people ask me how the drought and global warming is affecting winegrowers around the state. I wish I had a better answer, but I don’t really know, I am not sure if anyone really does. What I do know is that the vines in Napa are starting to bud; this is early, very early. This is about a week ahead of last year and about 3 weeks ahead of normal.…