Southern California Rain?
Although it will not be widespread, some rain will be possible in far Southern California and portions of western and southwestern Arizona before the week is over.
The culprit is Tropical Storm Paine in the eastern Pacific. You can see where Paine is located in the satellite image. Over the next few days, Paine will track in a northerly direction. Even though Paine will be weakening as it moves north, it will be able to spread some badly needed rain into portions of Southern California and Arizona.
Most computer models move what is left of Paine into the Southwest USA. It is fairly common in September for some eastern Pacific storms to work their way into the Southwestern states.
The far southern and southeast counties of California, even the deserts and areas of far western and southwestern Arizona will have the best chances for measurable rain.