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An Expert Explains: What Exactly Should Los Angeles Expect From This Winter's Brewing El Niño?

Bill Patzert had a busy 2015. As far back as August, the NASA JPL climatologist has been warning Los Angeles about this winter's El Niño phenomenon—which is promising to be so strong, he's calling it the Godzilla El Niño. According to Patzert, the storms brewing in the Pacific are taking a similar shape to the storms brought in by El Niño in 1983 and 1998. In both those years, Los Angeles received over 31 inches of rain, more than twice the average yearly rainfall. But so far, the winter hasn't been very wet in Southern California; the first El Niño storms are only due to hit this week. So are we headed for an unusually wet winter this year? Will it be enough to finally bust LA out of it's historic drought? Are we ready for all this rain? Right before the new year, Curbed got Patzert on the phone to get the skinny on what Los Angeles can expect from El Niño in 2016.

Curbed LA: You must be pretty busy these days.

Patzert: Yeah, I am. I'm over my head actually.

Curbed LA: What kind of timeline can we expect for increased rains this year? When will they begin and how long do you think they will last?

Patzert: So far, November and December turned out to be very very dry. They just started counting the rain year from October 1, so since October 1 in Downtown LA, we've had about an inch, which is 30 percent of normal for that date. We should be over three inches by this point.

Curbed LA: And that's due to the drought?

Patzert: Yeah. So at this point, the story is "the drought continues." Looking at past events, particularly the winter of '83 and the winter of '98, in 1998, the real rain started in February. In '83, the two big months for rain were January and March. So, historically, storms with over an inch of rain in 24 hours, they begin after the new year. Right now, we're getting a few sprinkles out of the north.

Curbed LA: But not the big one.

Patzert: No, we're still super duper dry.

Curbed LA: Will we see days where we have massive amounts of rainfall in a short period, or can we expect just a consistent normal rainfall?

Patzert: Let's look at February 1998 as an example. In February of 1998, we had about 14 inches of rain in the month. So, we had a year's worth of rain in one month. That was four big storms and two small storms, but in actual fact, there were 14 dry days and 14 wet days.

Curbed LA: So, half and half, then?

Patzert: Yeah, so during that month, the largest we had was about 2.2 inches of rain in 24 hours. That was on the fourteenth. And then we had five days where there was about an inch and half of rain. That's six pretty wet days there. Then we had three days where it was a half-inch in 24 hours, and then we had some modest ones, five days where there was a quarter of an inch of rain. But really in terms of soakers, it was only six days. We've had massive storms in Southern California where we had 10 inches in 24 hours, so I would call these steady and well spaced.

Curbed LA: That's a little more easy to deal with as a city.

Patzert: That's right, but the problem is, it keeps coming. So, you get an inch and a half, a couple of dry days, another inch and a half, and pretty soon everything gets to be pretty soggy and unstable.

Curbed LA: That's where you get into the mudslides and floods?

Patzert: Exactly, and trees falling down.

Curbed LA: Do you feel Los Angeles is ready for El Niño?

Patzert: We had a big flood in 1938 where we had 10 inches in 24 hours. Everything south of Downtown LA was underwater for two miles on both sides of the LA River. Irvine was under six feet of water. So, what we did was, we decided to concrete all our rivers and turn them into flood control channels.

Over the last 75 years, we've spent billions of dollars on flood control. In Los Angeles itself, the LA River, which is now the LA flood control channel, is 51 miles of concrete connected to 2,600 miles of storm sewers, and it works pretty well. In terms of large scale regional flooding, it's not gonna happen.




LA River before and after it's transformation into a flood control channel via Los Angeles Public Library Photo Collection

Curbed LA: But there will be some El Niño-related headaches around town, right?

Patzert: Generally the problems are local. People that are living on lots that have a fantastic view on hillsides, people that are living too close to the ocean in Malibu or Seal Beach. They're zoned precariously. It's called risky living. Rich people like to live risky because they can afford insurance. And then when you have a clogged storm sewer and all of a sudden you've got four feet of water under an overpass on the 101. Or just generally where there's been too much construction with not enough flood control. But those problems are generally local.

There will be plenty of stories for journalists if this thing delivers. The smallest mudslide will be hyped to death on the evening news. You already see it. The other night I was watching and some poor guy had a water pipe up above his property and he ended up with three feet of mud in his house. You'll see a lot of that. A lot of small catastrophes.

Curbed LA: What can homeowners do to prevent those catastrophes?

Patzert: We've had two pretty large events in recent history, '83 and '98. Many people know what to expect, and they have built in catch bin basins and spillways, and they're already starting to sandbag. And I think generally the local government, because I've worked with an awful lot of them in the last few months...

Curbed LA: They're getting ready?

Patzert: The word is out. But remember, we've had a prolonged drought here, and the National Forest, that story is well known with all the horrific fire seasons we've had here lately. What people forget is when they turned off our sprinklers to conserve water, [the sprinklers] also maintain the urban forest. Hundreds of thousands of trees in LA. So there are a lot of dead and stressed out trees, and so as the ground gets saturated, and if you have a particularly windy day, there will be a lot of problems with diseased dead trees around these neighborhoods. What goes along with that is power loss. The trees go down on the power lines. So some of the worst things that will happen are loss of power or a 100-year-old Eucalyptus falling into your bedroom or squashing your Prius.

Curbed LA: Oh no!

Patzert: So, we've put out a lot of warnings on the business with the trees. People have invested a lot of money in their roofs, but a lot of people couldn't because the roofers were so overcommitted.

What happens during an El Niño is that a high percentage of the basin goes to the tarps. Remember the blue tarps? I remember flying into LAX in February of '98, and it seemed to me a third of the homes had blue tarps on top. It was amazing.

Curbed LA: So, we can look forward to seeing a lot of blue roofs this winter?

Patzert: If you're in doubt at all about your roof, get your blue tarp and staple gun now, because that's your responsibility. That's not the city and county's responsibility. If the tree comes down on your Prius, that's also your responsibility, not the city and county. They've already done an awful lot for you, clearing flood control channels, catch basins, all these things.

Curbed LA: It's sorta on the homeowner to get ready now.

Patzert: At this point. Think back of what happened in '98 and '83.

Curbed LA: How do you think this El Niño will compare to the ones LA experienced in 1983 and 1998?

Patzert: Wouldn't this be ironic if January, February, and March looked like October, November, and December? That would mean it was a total unmitigated flop. Some people, whose names we won't mention here, are going to be publicly humiliated. So, at that point, when you call me, my phone is going to be disconnected, I'm going to be in the witness protection program. I will have already filed for a name change.

I and many of my colleagues are anticipating something similar to what we saw in the winter of '98 and the winter of '83, which by the time the large lady yodeled, rather than 15 inches of rain Downtown, it was 31 inches. It's an awful lot of rain especially when you consider how puny it's been in the last four and a half years.

Even today, it was a mess on the freeways, and I don't think we got a quarter of an inch.

Curbed LA: It doesn't take much.

Patzert: So one thing you can do to get prepared, make sure your windshield wiper blades aren't rotted out and don't be riding around on bald tires over the speed limit. The roofers should be doing a good business and the tire people should also be doing good business.

Curbed LA: Sounds like even if El Niño doesn't pan out, at least you've helped convince people to invest a little in their cars and homes.

Patzert: No matter what happens, the roofers are going to be happy, the tire people are going to be happy, the windshield wiper people, the tree trimmers, but in many ways these are all things that should be done anyhow.

Of course if it does happen, people are going to say, why didn't I listen to that dopey guy from JPL and buy three or four of those blue tarps?

Curbed LA: If we're talking about playing it safe, should people be looking into flood insurance too?

Patzert: At this point we're almost too late. The kind of flood insurance that comes with El Niño, that's not covered by your homeowners. That's a different policy, and it's through the feds. It takes 30 days to kick in. So we're near the stops now in terms of flood insurance. If you think you might need it, get flood insurance RIGHT NOW. You can always cancel it next year when we're back in the drought.

Curbed LA: Do you think this will put a dent in the drought at all?

Patzert: Oh yeah. It'll be a nice down payment, but it took us a decade and a half to get into this drought, and there's no quick fix. The other thing people don't realize is that 50 percent of this drought is just us. It's more industry, more agriculture, more population, more water demand, and more affluence. We got used to using too much water, so the natural drought, the mother nature drought, is only half the story. The other half is tremendous growth and affluence which has driven up the demand for water.

Curbed LA: From talking to you, it sounds as though our El Niño fears might be a bit overblown.

Patzert: It's a soap opera, El Niño. It exposes the soft underbelly of the civilization that we've built here. Seven out of 10 years in LA, if the average rainfall is 15 inches per year, seven out of 10 are below 15 inches. So, the bottom line is that when people ask me my forecast for next year, it's going to be dry! This year I had to change my tune.

But the people that really take it are the homeless. That's really the tragedy. I think this time, compared to '98 and '83, people have actually thought about it, and invested some money for shelters. They're starting to evacuate people out of river beds. Even living on the sidewalk, when it's February and you have 14 inches of rain, and it essentially it rains every other day, that's really unacceptable. That's just too punishing.
· There's a 95 Percent Chance SoCal is Getting Hit With a Huge El Niño This Winter [Curbed LA]
· How LA is Prepping to Take This Winter's Monster El Niño [Curbed LA]
· Mapping Everything You Need to Know About the El Niño-Powered Storms About to Hit Los Angeles [Curbed LA]