A quick update from my post yesterday. If you missed it, click here to view the complete post.
My thoughts have changed little, and the models continue to be pretty darn close through Tuesday. Expect well-below-normal temperatures Monday and Tuesday with a shower, even a thundershower, chance spreading east and south those two days. A deep marine layer in the Los Angeles and San Diego area Tuesday could mean a little light rain and drizzle in the morning hours, then an afternoon shower.
After Tuesday, the models part ways again with the European moving the center of the low east into the southern Nevada area with a trough hanging back over Southern California. However, the GFS still has a well-developed, closed low near Pt. Conception Wednesday and a little farther south over the Los Angeles Basin on Thursday. Obviously one model would have a better chance for a shower or thundershower than the other. As I explained yesterday, we are in a REX block and things evolve very slowly in these blocks. I am leaning more toward the slower GFS because of that.
No matter which model, there is at least two days for the chance of rain and temperatures are going to well below normal.
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.