Western rattlesnake or northern pacific rattlesnake.

Northern pacific rattlers scare me haha but you got a cool picture! Please consider adding it to the "Reptiles of the Pacific Northwest" mission!

looks like it's about to strike

Great spot Phillip! Welcome to Project Noah!
If you are confident that you have the correct ID, please can you look up & add the scientific name (this is really easy on Google) as spottings remain on the unidentified list until this box has been filled.
if you don't know or are unsure of the ID please tick the "Help me ID this species" box instead.

Hi Phillip5, welcome to Project Noah! You're starting a good collection of snakes! The Timber Rattlesnake is found in the eastern part of the US but the Northern Pacific Rattler is in your area. I'm looking forward to your next spotting.