A lot depends on what size pond, too.
You could always experiment with a small outside "bait" hatchery or something, and see how they fare.
I'm in Louisiana, and the weather is even more balmy than WA, and I wouldn't risk cherry shrimp outside, although ghost shrimp are common in some fresh waters, and of course, gulf shrimp (yum).
When I lived in PA, I had an outside pond I dug and dropped a liner. It was and irregular 8 ft. x 4 ft, 24" at the deepest. It had koi, assorted goldfish, turtles, frogs, etc.
Come October, it got so cold I basically shut everything down-turned off filter and floated a ball to prevent it icing over. I could see the fish thru the ice-motionless. The turtles would burrow underground and hibernate. (I know because I almost cut one putting in Spring flower bulbs.) Everything would "come alive" around April, and I would start everything up again. Had it for 7 years, then sold the house, and couldn't take it with me.
Oh, I was always an Eagles fan, and in Pa, it was always Eagles vs Steeler fans.
The first year I move down here, however, it snowed 2 inches and lasted all day.
And...the Saints won the Superbowl. I don't know which one was more miraculous