The weather pattern along the West coast from Washington state to California is very dull. In general, there is a ridge of high pressure at 500 mb in control.
This high is providing warm temperatures away from the immediate beaches but not excessively hot weather as we had in portions of Southern California late last week and over the weekend. Temperatures will be averaging above normal.
There is a broad and relatively weak, closed low well west of the southern Oregon/northern California coast. While this spins well offshore the next couple of days, it will eventually head east by Friday and the weekend. Models are in agreement on this. What they are not in agreement on is how far south the low will go. The main effect on the weather would be on how much cooler air occurs, especially in central and Southern California. Precipitation is not going to be much, though there could be a mainly afternoon shower or thundershower in a few spots over Oregon, northern California and northern Nevada. Monsoon moisture is not going to be a player.
This will make for a very hazardous period for firefighters into early Friday night.
With such high heat and low humidity, the fire danger will be as high as it can get.
For the second time this week, parts of northern California will get some rain.
With such high amounts of water vapor, thunderstorms will bring locally very heavy rain that can cause flash flooding.
Many areas east of the Cascades this weekend will be over 100 F.
some of the moisture from Andres and newly formed Blanca could influence the weather in the Southwest