At this point, it's snowing in the high country. While we saw them around 8000 feet last weekend and more lower, they weren't biting yet as it's still cold at night and they aren't ready to mate. The minute it warms up the females start to want blood and go nuts. So hope for cold nights to continue.
That depends on the elevation you are at. I would expect the 40s at Hetch Hetchy and lower than that if you're higher in elevation. In fact, I won't go anywhere above 7000 feet without being prepared for below freezing temperatures, even in the middle of summer, because it will get into the 20s without much weather involved.