El Nino Doesn’t Guarantee California Gets Drought-Relieving Rain

El Nino can mean devastation for some parts of the world. For California, this year, it means hope.

The hope is the state will get drenched and a four-year drought will release its grip. After all, Texas and Oklahoma got soaked in May and June and their multiyear droughts just faded away.

For that to happen in California would probably be a long shot.

“They didn’t get into this drought in one year and it takes time,” said Brian Fuchs, a climatologist at the National Drought Mitigation Center in Lincoln, Nebraska. “Texas and Oklahoma being the exception, typically you come out of it just as slow as you went into it.”

If that’s true, one year of normal rain would be a good start for California but not a finale.

As of last week, 98.7 percent of the state was experiencing some degree of drought -- all except a bit of the desert near the Arizona line, according to the U.S. Drought Monitor.

Nearly 47 percent of California is in the grip of exceptional drought, the worst of four categories. That’s up from a little more than 36 percent a year ago. If there is good news, it’s that the combined two worst categories, exceptional and extreme, now cover just over 71 percent, compared with almost 79 percent at this time last year.

Storm Track

El Nino, a warming of the equatorial Pacific, is being hailed as a hope because the changes it brings to the atmosphere tend to push the U.S. storm track farther south than normal, sending rain, sleet or snow across Southern California and its mountains.

Some models are forecasting that’s what will happen as 2015 turns into 2016. Of course, that’s a little like predicting a mother beagle will give birth to a pup with brown ears.

That’s what mother beagles do.

So what brings on such a naysayer attitude?

There are a lot of moving parts in this El Nino scenario.

Fuchs said there have been a few El Ninos that haven’t acted in typical fashion. And, as the U.S. Climate Prediction Center has pointed out, sometimes an El Nino is too strong and the storms are pushed too far to the south and rains fall in Mexico instead of California.

Then there is the temperature.

Heat Variable

In 2013, California had its 11th warmest year on record, according to the National Centers for Environmental Information in Asheville, North Carolina. In 2014 it had its warmest, and this year is shaping up to set another record.

High temperatures mean people, animals and plants demand more water, Fuchs said. It also means that what would have been snow in other years falls as rain.

Snow is like gold in California’s water bank because it can be stored in the mountains through the winter, when it isn’t needed for agriculture, and then run down in the spring when it is.

California gets most of its rain from November to April and almost nothing from May to October. If someone needs water for crops or drinking in July, it had to have been stored over the winter.

So, is El Nino going to bring the water?

“There’s a lot that needs to happen to get to that point,” Fuchs said.

The conventional wisdom doesn’t seem quite so certain anymore. Which reminds us of an old saying: What kind of person bets on the weather? A poor one.

Before it's here, it's on the Bloomberg Terminal. LEARN MORE