I have the Arc'teryx Aphix hoody, which is by no means stormproof or waterproof, just has a DWR coating, but it's kept me dry so far. Wouldn't want to be caught in a severe downpour for many hours with it. I think it's discontinued now. I primarily use it for skiing. Listed weight 17 oz.
As for the pants, I'm using GORE Fusion 2.0 Gore-Tex Active pants, which are rain pants for cycling, but work great for backcountry skiing and mountaineering. Listed weight 247 g = 8.7 oz. I've glissaded in them and torn the butt, but a small gore-tex repair patch fixed 'em right up.
The down jacket I'm using is the Sierra Designs 800 fill DriDown Gnar Lite, listed weight 11.2 oz. / 317 g. I'm thinking about getting the hooded version...
