Even though a strong El Niño is in progress and likely to last for months, the prospect of drought-busting rainfall is not a guarantee for California this winter.
The Climate Prediction Center of the National Weather Service suggests that a "Godzilla El Niño" may be on the way this winter.
However, how much rain and snow California as well as other areas along the West coast receive will be dependent on the interaction between El Niño and other conditions in the northern Pacific Ocean.
El Niño is the warm part of a warm/cool cycle of ocean water temperatures in the tropical Pacific that spans several years.
All other conditions being average, a strong El Niño tends to fortify the winter storm track over the northern Pacific and can allow strong storms, loaded with moisture to blast onshore over the West Coast of the United States.
In order for there to be a strong storm track, there needs to be a large temperature contrast from north to south. Here lies the potential problem for forecasting once-in-a-lifetime storms in California this winter.
Waters over the northern Pacific, particularly from Alaska to California, are also warm. The cycle in this part of the Pacific takes many years to run its course.
The effect of the warm waters in the northern Pacific could counteract some of the impacts of a strong El Niño. This winter's El Niño could become the strongest in more than 50 years.
According to Long Range Meteorologist Anthony Sagliani, "The wrath of storms produced during the record El Niño of 1997-98 occurred when waters over the northwestern Pacific were cool, not warm like we are seeing now."
Warmer-than-average waters in the northern Pacific tend to pull the storm track farther north, while El Niño tends to pull the storm track farther south.
What may happen in California this winter is that more modest storms could deliver episodes of soaking rain, rather than many storms with torrential rain, yards of snow in the mountains, damaging winds and major flooding.
While moderate storms with less flooding rain and damaging news would be good news for property owners and commuters, it would take several blockbuster storms to build snow levels significantly and fill reservoirs in order for more lasting drought-relief.
AccuWeather Chief Long Range Meteorologist Paul Pastelok stated you have to go back many decades before you can find a similar setup to what we believe will transpire this winter.
"The 1957-58 El Niño is the closest match to conditions we are seeing now and what may happen this winter," Pastelok said.
For example, in Los Angeles the total rainfall for the year in 1958 was 15.43 inches, compared to 27.06 inches in 1998 and the normal of 12.82 inches.
Since rainfall deficits are currently extremely large in California, the tradeoff may be that near- or slightly above-average rainfall occurs and the drought is still intact by the end of the winter, but perhaps just not as extreme.
In many locations of California, the rainfall deficit ranges from 1-2 feet below average since July 1, 2013.
People will still need to keep conserving water and be prepared for significant and disruptive storms this winter.
According to AccuWeather Senior Meteorologist Henry Margusity, "The challenge meteorologists face this winter is the pattern is much more complex than whether or not there is an El Niño with big storms."
The realm of possibilities this far in advance ranges from a spray of storms along the coast from California to Mexico and minimal drought relief to relentless storms in a narrow zone producing flooding.
Until El Niño storms and rain kick in this winter, wildfire conditions will continue to worsen over much California into this fall.