That's actually a difficult question. I like it cool, not hot or cold...like lower 60's. I actually don't mind a gray, drizzly day. I have very good memories of gray, drizzly days. When I was a teen my family took one of those long travel-trailer vacations to the pacific northwest. I LOVE it there. I remember walking on the beach and picking up sand dollars and I was wearing shorts and a jacket and freezing! But it was so refreshing. And we explored the redwoods, wandering down trails and everything was cool and green. When I was in my 20's I went to visit an aunt in Seattle and it was like 100 degrees in Missouri, and 65 and rainy there and I loved every second. I lounged on her pergola covered patio, which was covered with hanging fuchsia plants in bloom, and napped and relaxed. It was perfect napping weather. The PNW is my favorite place in the whole world. I'd SO love to go back.
But I think my favorite are the cool, crisp, dry days of Autumn, when the leaves just start turning and the hot, muggy summer has ended.