Columbia Silkmoth Larva

Thanks for the info. Glad to get some results :)

Kristen - My first thought was a Cecropia Moth larva, but you're a bit too far west for that, so that led me to the Columbia instead. The caterpillar shown here doesn't exactly match the picture at the link I've provided, but moth caterpillars are often pretty variable both throughout their lives and even from one area to another. Nice spotting!