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.
These is the possibility that another surge of tropical moisture could move into Arizona and Southern California by the middle of next week.
I still believe the greatest amount of rain, at least partially relating to Norbert, occurs from southeast California to Arizona
The effects on Southern California are very much in question.
With low wind shear and warm water in its path for a while longer, it is likely that Norbert intensifies into at least a Category 2 storm.
For much of the last week the monsoon moisture flow into the Southwest has been completely shut down by dry westerly winds. This is about to change.
A big pattern change is underway, one that will completely shut down any chance of showers and thunderstorms for an extended time period.