OK... So if the OP does end up in Seattle over three consecutive days of bad weather, here's an oddball option for walking the city streets in the rain without getting wet. You won't find this photo-op in too many cities:
And here's a background video from The History Channel with some of the backstory (the part about flushing the toilets is sadly true):
It's a standard Seattle touristy thing to do. But it's also a bit of a unique touristy thing with interesting historical anecdotes. Not everyone's cup of tea. And definitely not doing flower pictures in gardens. But worth doing if you haven't already at least once before. And, like me, you enjoy oddball adventures.