Look! It's even kind of sunny right now! Look at all that blue sky!
Seriously, in just about every episode of that show it looks like Seattle is in the middle of monsoon season.
Here's an excerpt from a Wikipedia article (which we know is always super accurate).
"At 944mm (37.49 in.), in reality, the city receives less precipitation annually than New York City (1201 mm, 47.28 in.), Atlanta (1290 mm, 50.79 in.), Boston (1055 mm, 41.53 in.), Baltimore (1038 mm, 40.87 in.), Portland, Maine (1128 mm, 44.41 in.), Jacksonville, Florida(1304 mm, 51.34 in.), and most cities on the Eastern Seaboard of the U.S. Seattle was also not listed in a study that revealed the 10 rainiest cities in the continental United States."
It certainly does rain in Seattle, and we joke that only tourists use umbrellas because we're hardened to being constantly drenched. But even in October/November, the months this show is set in, I'm pretty sure (and seeing as how I live in the area my 'pretty sure' is basically 'I know for a fact') that it doesn't rain as much as they would like us to think.
But seeing as how these poor sods live in a fictional Seattle that is constantly plagued by torrential downpours, I'd like to suggest some rain gear that I first came across in April of 2008:
I think everyone in The Killing should wear this every time they go outside. The Nubrella is now only $49.99! I mean, just check out this promotional video and tell me this wouldn't be a brilliantly effective, stylish, and practical solution for our sad, dripping wet friends as they rush around the city trying to catch a murderer:
Ah, yes. Such an elegant solution.