Memorial Day is not a dependable weekend around the Northwest...never has been, never will be. Generally we have a sunny, warm period in the middle of May (early May this year) and then we move towards the June gloom mode of low clouds.
During the past few days we have had a closed upper low hanging over us (see graphic), with showers circling around, sometimes from the unusual easterly direction.
Saturday will be bring clouds and some light rain showers over and west of the Cascade crest. Here is the 24 h total precipitation ending 5 PM on Saturday. Not the best day for a hike on the western slopes of the Cascades, and the Oregon coast will be damp.
One good thing about the cool, damp period of the past few days has been a substantial freshening of the snow about 3500 ft. Some good late-season cross country skiing and the Cascade and Olympic Mt. snowpack is well above 100% of normal.