The event in Redmond, WA, is called Exotics @ Redmond Town Center. It's basically a Cars & Coffee for exotics. They meet every Saturday morning, weather permitting, from 9-11am, officially, but it is best to arrive about 8:30 to get parked well and to see the other cars arrive. Your Lotus will get you in - there's no charge. You'll see some nice cars.
The best way to stay informed on that recurring event is to look for them on Facebook - search for [email protected] - where they provide the latest news on their activities (cancellations, directions, special events, etc.). Their first meet is April 2nd and they run into the fall. They have a British Car Day on May 21st.
There is the Western Washington All-British Field Meet at St. Edwards Park in Kenmore, WA, on July 23rd.
The Seattle Lotus Club, Evergreen Lotus Car Club (ELCC) and the Portland OR club, Club Lotus NW (CLNW), have Googlegroups that discuss various events in their respective areas.
I went to the West Coast Lotus Meet in Seattle in 2013. It was a blast! It doesn't look like they have solid plans this year (and in years past it's been in other locations). You might want to keep an eye on it: West Coast Lotus Meet