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El Nino event takes longer than expected to bring needed rain

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For about a year, we’ve been promised “torrential downpours”… “buckets of rain”…“sheets of storms” and, most importantly, “drought relief.” But now that Southern California is broiling in 90-degree heat in traditionally the wettest month of the year, everyone is asking: “What happened to El Nino?”

The “little boy” that was supposed to quench our climatic thirst has apparently vanished. Climatologists have warned how warming ocean temperatures in the Pacific would fuel a punishing series of storms landing blows up and down the California coast from December to April. Howerver, so far there have been two or three local rain storms (including light showers late Wednesday), a welcome snow pack at the ski resorts, the expected snowfall in the Sierra Nevadas, but not the deluge anticipated throughout the Los Angeles Basin.

‘Be patient’

This El Nino is already acting differently from the last big one in 1998. Scientists don’t quite know what to make of the delay, but most are sticking by their forecast that the storms will occur … just a little later than predicted. Practically all of the rain that was supposed to hit California has headed far into the Pacific Northwest. That last-minute diversion has left Southern California under a high pressure system that has delivered one month of hot, dry weather and produced red flag alerts in the foothill areas and burn zones such as Glendora. However, the delay locally has helped to replenish the snowpack in the Sierras and Rockies—prime sources for local fresh water—and as far north as the Cascades, with the latter region experiencing it’s own unusually dry, wildfire-filled summer.

Consequently, California’s largest reservoirs are filling up and the snowpack is at a statewide average of 103 percent for February (the average is 150 percent by April 1, when snowpack levels typically peak). However, one-third of the state remains in exceptional drought.

Television meteorologists, climatologists at the Jet Propulsion Laboratory (JPL) in La Canada, and scientists  at NASA have been fielding calls daily since late January about the “no show” El Nino. They have a pat answer: “Be patient.”

‘Show me the rain’

“No matter where I go—whether it’s JPL or Whole Foods or talking with reporters—everybody has a simple question: ‘Show me the rain,’” said Bill Patzert, a climatologist at the JPL. He said expectations may be outrunning El Nino because the region has gone dry for so long, practically any official mention of rain gets immediate attention. Patzert explained that the massive pool of warm water still parked off Central America’s coast remains as formidable as the 1998 El Nino, but is “taking its sweet time” to arrive. The JPL has a satellite called Jason 3 and each day that Patzert looks at the latest image of El Nino, he said it resembles a crocodile, complete with an eye and even a tapered snout. And the “croc” has legs, he said, noting that this year’s El Nino is “… definitely longer lasting and reaching its peak much later” than it did in 1998.

“Don’t mock the croc,” Patzert warned, “it’s still a big deal.” Patzert explained that, historically, El Nino has put on a “big show” in February and March, but cautioned that accurately predicting the weather phenomenon is tricky business. El Nino is behaving much like the typical taciturn toddler who says little at first … and then lets loose big time. “By late February, I’ll be nervous, if something hasn’t happened,” he said.

Pre-noon heat records were set this week across Los Angeles County. The temperature approached the 70s at that hour in both Lancaster and Palmdale, which is unseasonably warm for February. In nearby Sandberg, a recent high of 68 degrees broke a 65-year-old record. A brief storm on Wednesday brought showers and 50- to 70-mph winds to the Antelope Valley. And while El Nino conditions are causing massive snowstorms in the Northeast and flooding in the Midwest, much-needed precipitation is still missing locally. The National Weather Service said at the beginning of the month that El Nino is simply taking a “five- to 10-day break” and that forecast failed considerably. In the meantime, the high pressure—or “ridiculously resilient ridge” in meteorological parlance—has resulted in strong Santa Ana winds, which have forced fire agencies to warn of sudden brush fires. Unexpected, strong offshore winds have been gusting off the mountains to 40, 50 and 60 miles per hour which have increased the temperature even further.

Not the ‘typical’ El Nino

Kevin Trenberth, a climate change and El Nino expert at the National Center for Atmospheric Research, said that while this is technically a strong El Nino, it is not playing out as expected. Perhaps, he explained, people tend to be too focused on temperatures of specific regions and not the big picture.

“This El Nino has been called ‘very strong’ and one of the top-three strongest on record,” Trenberth said. “That is true, if one measures it only by the warmth in the eastern tropical Pacific. But most El Ninos also feature a cooling in the western tropical Pacific, and that is largely absent this year.”

As a result, Trenberth said, the differences in temperature along the equator are much less than previous El Ninos, and the reversal in the trade winds that blow across the tropics is considerably weaker than what the county saw in the winter of 1997-98, when there was about 14 inches of rain in February alone. Also, a lot of  weather changes or “action,” Trenberth said, taking place in the Indian Ocean is interfering with Pacific Ocean activity. Add all of this information together and it appears that all bets may be off about “typical” El Nino weather patterns, and it’s entirely possible that we may have witnessed the peak winter rainfall come and go.

Blame it on high pressure due north

“A consequence of this is that the activity in the eastern Pacific has been nowhere near as strong as predicted, and in fact it disappeared a couple of weeks ago,” Trenberth noted. “It’s the eastern Pacific activity that tends to have the most influence on Southern California storm tracks.”

The Southern California landscape is well below average rainfall, with downtown L.A. reporting just 52 percent of normal since Oct. 1. While El Nino so far has not been the great predictor of winter weather, Daniel Swain, a climatologist at Stanford University, explained that previous models may not be reliable this season because the storm system has not influenced the atmosphere the way it usually does. Again, he said it’s simply “wait and see.”

“With the zone of warm water in the ocean particularly large and persistent, the movement of warm air above it traveled farther north than expected,” Swain said. “That means that the parade of storms zipping across the Pacific Ocean established a path over Northern California and even the Pacific Northwest—and bypassed Southern California.”

Swain further explained that there is the possibility that this El Nino is too big, meaning that the large storm system that blew through in mid January was only a remnant of a larger system that delivered heavy downpours over Northern California. “That’s a real possibility,” he said. “We knew this would be one of the most potent El Ninos in decades, but the sheer magnitude and size means that it won’t focus specifically on Southern California. It may be because [this] El Nino is so strong.”

‘Serious rain’ in about two weeks

The National Weather Service’s Climate Prediction Center (NWS) in College Park, Md., released last week its monthly El Nino forecast, predicting a 50- to 60-percent probability of above-average rainfall in Southern California for March and April. The forecast basically reiterated a prediction of El Nino-patterned weather for the region, namely the weakened, westward-blowing trade winds and a warming of the upper ocean in the central and eastern Pacific well after the jet stream, thereby pulling storms into the West Coast region much like what happened in February-March 1998. Another persistent high-pressure system over Utah has brought additional dry, hot weather into the Southland over the past two weeks. This system, or “high pressure dome,” has reportedly pushed the jet stream north and that’s the reason why so much rain has fallen in the north, and so little here.

John Gottschalck, chief of the NWS operational prediction branch, said all of this information is part of a “short term” phenomena, adding that his office has predicted a “slight chance” of showers this week. Serious rain, he said, is not expected until the end of the month and into March.

“There may be more stormy patterns as we enter March,” Gottschalck said. “The ball game is not over yet … we still have lots of innings left in the game. We still have March.”

Practically all scientists who have been monitoring El Nino say it will perform. After all, the storm system is reportedly 2 1/2 times the size of the United States and has actually shrunk about 40 percent since the last NASA image capture on Jan. 23. At the beginning of the month, the weather system had begun to recede east of Hawaii; prior satellite images showed it just off the western portion of the islands. At the JPL, Pataert explained this shift as normal for an El Nino this size, noting “as this [signal] shrinks, the jet stream should pull farther south and track the storms into southern California,” he said.

Ken Clark, a meteorologist with Accuweather.com, insists that El Nino will arrive with the anticipated hard punch. The change in the weather pattern, expected around the first week of March, will begin to bring the storm track farther south and across more of Southern California. This is not the time, he cautioned, to put away the umbrellas and rain coats.

Flood insurance good idea

“No, it hasn’t gone away. It’s as strong as it ever was,” Clark said. “We still looking at late February through March and possibly into April. The heavy rains will likely arrive a month or so later than predicted. It’s not unusual for El Ninos, in regard to Southern California rain, to be slow starters, but when they arrive they are ‘fast and furious’ finishers.” Clark said the high-pressure system over Utah generally caught meteorologists by surprise, noting that the “short-term” phenomena is fading by the day and portends good news for a dry, parched Southern California.

Of course, flood insurance is a good idea—so much so that there were more than 285,000 National Flood Insurance Program policies taken out in California at the start of the year. This represents a gain of about 25 percent above the number of policies as of Aug. 31, 2015, signaling the largest jump for the state since the flood insurance program was created in 1968. The Federal Emergency Management Agency (FEMA) has seen 127 flood insurance policyholders in California submit claims in January alone, compared with only one claim submitted statewide in January 2015.

“What we’re really encouraged about is people are taking steps to prepare themselves,” said Mary Simms, a FEMA spokeswoman. “If we use the last El Nino season in 1998 as a guide, it was not until spring that we saw damages that warranted a presidential declaration of a disaster.”

Patzert of the JPL is taking it all in stride. El Nino pessimists within the public and media, he said, tend to have an “unquenchable thirst” for colossal storms and massive mudslides.

“A month from now you’ll be writing about the ‘March Miracle’ or ‘April Apocalypse,’” he said.

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