1 day Seattle trip
Depending on mode of transportation available to you...
If you have a car or can tolerate the bus system, check out the various eclectic sculpture art in the Fremont area - the troll under the Aurora Bridge and Lenin are local icons and can make for interesting photo subjects even in wet weather. Or check out the more formal Olympic Sculpture Park at the north end of Alaskan Way - potential for Calder with a mountain background.
If on foot and downtown, keep wandering south on 1st from the Pike Place Market and find some interesting old town architecture around Pioneer Square.
Take the West Seattle water taxi to cross Elliott Bay from the downtown ferry terminal for great shots back across the water of the Seattle skyline. Free shuttle from there to Alki Beach - nice views, relics of the historic beginnings of Seattle and the bald eagles are showing up more regularly now.
Have fun and stay dry!