Perhaps something in the genus Cardamine.

Most likely in the mustard family. I'm not familiar with western plants but it resembles some species of Arabis

Perhaps Cardamine hirsuta, hairy bittercress. I'm weeding it a lot around here, though it's almost too late as it's going to seed.

Here is a link that might be useful: Cardamine hirsuta

I have this in WNC -- or something very like it. This hairy bittercress is the closest ID I've yet found (I'll have to check to see if mine is hairy).

When conditions are bad, it can set seed at about 1 1/2 - 2" tall. Cute, but you don't want to let it get a foot in the door....

Thanks, everyone! I can now provide the name to my neighbor who was asking me just last week what it was.

Thanks for all the tips so far. I did look at the Bittercress family and ruled it out because of the leaves. I wish I had taken a good picture of the base and will return to this area next week and try to do so.

The best way I can describe them is the plant was about twice as tall as Spring Drapa and had a whorl of leaves at the base that looked very similar to the ones on Spring Drapa (Drapa verna)

Because of this, I thought it was Spring Drapa at first glance, but the petals were not notched and it was a little taller, although it had very slender, leafless stems like Spring Drapa. I'll try and get a better picture of the entire plant when I return to the area - bper

Cardamine bulbosa was one that I identified earlier in Georgia. It looked a lot like this.

I have found one plant in the Cardamine family that might be close. It is called Alpine Bittercress (Cardamine bellidifolia). It is found just the North and West of Yakima county where I found the sample. I need to look closer at the leaves. This variety has a rosette at the base similar to the plant I found. Link below to the info on it - Bruce

Here is a link that might be useful: Cardamine Bellidifolia