Will this jacketkeep me dry in tropical...
Will this jacketkeep me dry in tropical rainstorms? Any suggestions of a light weight rain jacket that will?
No, it's only water resistant. With rain gear, you'll get what you pay for. Sorry I'm not familiar with the Sierra Designs stuff, but you'll want something that's "waterproof" (including taped seams)and that breaths well. Maybe start there. Also, have a look at the something like the Marmot Precip as your next step up in price, weight, and quality. Rather than send you in the direction of Gore-Tex, since the conditions you're asking about are tropical, and undoubtedly hot and humid, I would suggest something in eVent. The right piece will keep you dry and breath well enough to keep you cool. My favorite jacket is the Rab Latok Alpine. It's what I use most often, and the first thing I would reach for in your situation. Hope that helps.