The Climate Prediction Center's outlook for September, October, and November of this year in the next map shows above-average rainfall likely over Arizona and into California as well as other areas of the Desert Southwest. Recently, an AccuWeather post for Fall 2015 also held out a bit of hope by saying, "An expected strong El Niño will lead to beneficial rain for Southern California, but it may be delayed until late fall and winter."
In this post, I'll consider some dates when drought conditions may be alleviated based on planetary cycles that culminate in September of this year and are then triggered later in October. The main player is the Jupiter-Neptune opposition of September 17, 2015. At the time of their opposition, they will be over 119 degrees west longitude through California.
From another perspective, the New Moon of September 13th places them along 112 west longitude through Arizona. The conjunctions and oppositions of Jupiter and Neptune induce isolated torrential downpours and are potential flash flood breeders according to G. J. McCormack, the 20th Century's ablest astro-meteorologist. So there is the potential that around the 17th of September we may see precipitation over this area as well as around September 26th when the Moon will conjoin and oppose this degree. But I'm even more concerned about a couple of dates in October.
On October 6th, Mars will oppose Neptune--another combination known for producing semi-tropical low pressure areas. This opposition will fall right on the Jupiter-Neptune opposition of September 17th mentioned above. Hence, this could be another period--in and around October 6th--where beneficial rain is seen over California. To a lesser extent, when Venus and Neptune oppose each other on October 16th and activate the same Jupiter-Neptune aspect there may be more moisture flowing in over the same area.
Links to Other Long-range Weather Forecasts and Forecast Results
Hurricane Dolores Fulfills Long-range Weather Forecast
Hurricane Season 2015 Long-range Weather Predictions
Tropical Cyclone Hadi
Hurricane Erick Fulfills Long-range Forecast
Tropical Storm Andrea Fulfills Long-range Forecast!
Timing the Relief for Drought-Stricken U.S. Plains
Testing Astrometeorology Part 2
Hurricane Sandy Fulfills Long-range Weather Prediction!
Testing Astrometeorology Part 1
Hurricane Season 2011 Forecast Results
New Weather Alternative Website
Fulfilled Long-range Forecasts for Hurricane Season 2010
Introduction to the Weather Alternative