El Niño has arrived. What does it mean for the weather?
By Jeff Berardelli
/ CBS News
It's official, an El Niño advisory is now in effect for the globe. After several months under a "watch," teetering on the edge of El Niño, NOAA's Climate Prediction Center (CPC) has finally pulled the trigger.
The climate phenomenon may enhance an already very stormy pattern across California, making it even stormier.
The El Niño Southern Oscillation is a natural cycle of warmer and cooler than normal Equatorial Pacific Ocean temperatures. The El Niño phase is a warming of the Central and sometimes Eastern Equatorial Pacific sea surface temperatures, occurring every few years on average.
It's here! Today @NOAA declared that #ElNino conditions are now present. Read more at: https://t.co/frHgtyNIdq pic.twitter.com/ZZyzaPoK4c
— NWSCPC (@NWSCPC) February 14, 2019
By definition, sea surface temperatures are only required to be 1-degree Fahrenheit above normal to qualify. A warming of that seemingly small amount can send feedback into the atmosphere, helping fuel atmospheric rivers and strong sub-tropical jet streams like the one pummeling California right now.
An atmospheric river is bringing heavy rain and mountain snow to #California. Check out the conveyor belt of clouds and moisture heading toward the West Coast in this loop from our newly operational #GOES17 (#GOESWest) satellite. Learn more: https://t.co/DhXRshmtyJ pic.twitter.com/fix8G2myrO
— NOAA Satellites (@NOAASatellites) February 13, 2019
The decision of whether or not to make it official is based on a variety of different technical criteria. But CPC determined as of Thursday those criteria are met, "based on the presence of above-average sea surface temperatures across most of the equatorial Pacific Ocean and corresponding changes in the overlying atmospheric circulation."
Dr. Anthony Barnston of the International Research Institute (IRI) for Climate and Society at Columbia University is a leading expert on El Niño and helps craft the forecast. He says that last part — corresponding changes in the overlying atmosphere — is what had been lacking since the fall. He explains, "Ocean temperatures have been warm enough in the El Niño regions for months but until recently we did not have enough ocean-atmosphere interaction. Now we do."
What will El Niño mean for the weather forecast?
So, will this make for a stormy pattern across the U.S.? Dr. Andrew Robertson, also of IRI, is cautious, saying that much of the recent stormy weather in the West "does not seem to be El Niño related."
Robertson connects most of the unsettled weather to a vigorous jet stream dropping south along the Pacific Coast "that is steering cold storms southward — hence the unusual snow in Seattle." Up to this point what we have seen "is almost the reverse of the typical El Niño pattern of a trough over the Pacific and Pineapple Express storms over California."
But the appearance of the Pineapple Express — a jet stream that starts near the Hawaiian islands — over California right now may mark a subtle shift in the pattern, to one with more El Niño-like impacts.
The weak El Niño is expected to continue for a few more months. Barnston says that may have limited impacts on weather as we close out winter.
Typical El Niños tend to be wetter than normal in Southern California and eastward across the southern U.S. from Texas to the Southeast. So the upcoming weeks may see increased storminess from El Niño in those areas. Considering the already saturated ground across California, more precipitation would likely mean more flooding for coastal areas and piles of heavy snow in the mountains.
"It will be interesting to see how things evolve," notes Robertson.
First published on February 14, 2019
© 2019 CBS Interactive Inc. All Rights Reserved.
Jeff Berardelli
Meteorologist Jeff Berardelli is a CBS News Climate & Weather Contributor. Follow him on Twitter @WeatherProf.
How to watch the Daytona 500 this Sunday
The Great American Race kicks of the NASCAR season
updated 7M ago 
Shutdown watch: Senate passes border bill, Trump to declare emergency – live updates
The Senate passed the bill Thursday afternoon, and the House is expected to pass it in the evening
updated 11M ago 
El Niño has arrived. What does it mean for the weather?
After several months on the edge, we're officially under an El Niño advisory
updated 15M ago 
"Since Parkland" profiles 1,200 kids killed by guns
More than 200 teen reporters told the stories of young lives lost to bullets
updated 24M ago 
Senate passes bill to fund government, avert shutdown
The measure is also expected to pass in the House and signed into law by President Trump
updated 47M ago 
Shutdown watch: Senate passes border bill, Trump to declare emergency – live updates
The Senate passed the bill Thursday afternoon, and the House is expected to pass it in the evening
updated 11M ago
Senate passes bill to fund government, avert shutdown
The measure is also expected to pass in the House and signed into law by President Trump
updated 47M ago 
GOP lawmakers blast McCabe for comments in "60 Minutes" interview
Republicans balked at fired former FBI deputy director Andrew McCabe after his explosive interview with CBS News
1H ago 
Immigration advocates sue DHS and others over "Remain in Mexico" policy
The initiative is possibly the biggest change to immigration policy implemented by the Trump administration
1H ago 
Trump to declare a national emergency for border wall
The Senate majority leader says the president will move ahead with his long-threatened move to declare a national emergency
updated 8M ago 
Immigration advocates sue DHS and others over "Remain in Mexico" policy
The initiative is possibly the biggest change to immigration policy implemented by the Trump administration
1H ago 
Pompeo: Trump administration doing "everything" it can to free Americans in Iran
"We're having conversations with all the people who have the ability to help get them back," Pompeo said
updated 2M ago 
Duchess shines light on dangers of osteoporosis
Camilla, 71, opened up about her late mother Rosalind, who died of the bone disease in 1994
3H ago 
Human foot found on Canadian coastline — the 15th since 2007
Authorities are seeking help identifying a foot found inside a Nike sneaker
1H ago 
Pompeo refuses to say if he believes CIA on Khashoggi killing
Dismissing the question as "ridiculous," Pompeo says U.S. will hold "each individual accountable" for the murder, but current "fact sets" don't implicate crown prince
8H ago 
Alfonso Cuarón on the personal trauma he channeled into "Roma"
The black and white foreign film with a largely unknown cast has become an unlikely Oscar front-runner.
4H ago 
Ryan Adams accused of emotional abuse, sexual misconduct
In one allegation, a 20-year-old female musician said Ryan Adams, 44, had inappropriate conversations with her while she was 15 and 16
1H ago 
These A-listers are the most stylish stars, according to People
Ahead of the Academy Awards, People has released its list that also includes Emma Stone, Nicole Kidman, Donald Glover
22H ago 
Disney reveals first look at "Frozen 2"
Fans get their first look at the highly-anticipated "Frozen 2," and it appears the cast is far from where they started
Feb 13 
3 women share role of Cher on Broadway. They call it "Cherapy."
The lead role is played by three actresses who represent the different stages of Cher's life
Feb 13 
El Niño has arrived. What does it mean for the weather?
After several months on the edge, we're officially under an El Niño advisory
updated 15M ago 
Dating apps expose lovebirds to scams and hackers
Mobile apps have transformed the dating experience but they can also expose sensitive information to fraudsters
5H ago 
Solar jobs are on the decline — the industry blames Trump
U.S. tariffs have cast a shadow on what until recently had been one of the country's hottest job sectors
6H ago 
California governor: Consumers should get paid a "digital dividend"
The idea is sparking debate about a tax on tech companies or a refund to customers who share their data with Facebook and others
7H ago 
Hackers are stealing medical records – and selling them on the dark web
How easy is it for criminals to get hold of these patient files? It only took a few seconds
8H ago 
Could diet soda raise a woman's stroke risk?
New research looks at the possible connection between diet sodas or artificially sweetened fruit juices and heart health
updated 11M ago
Duchess shines light on dangers of osteoporosis
Camilla, 71, opened up about her late mother Rosalind, who died of the bone disease in 1994
3H ago
Hackers are stealing medical records – and selling them on the dark web
How easy is it for criminals to get hold of these patient files? It only took a few seconds
8H ago 
CDC warns about potentially contaminated raw milk
A dangerous drug-resistant bacteria is connected the consumption of raw milk in 19 states
Feb 13 
Eating these kinds of foods may cut your life short
New research suggests certain foods high in salt, sugar and other additives may increase the risk of early death
Feb 13 
Tax refunds are lower for second week in a row
Returns are being processed more slowly, and the average refund is about $185 below its level last year
updated 38M ago 
Federal revenue fell in first year after U.S. tax overhaul
The government is taking in less money from businesses and individuals even as the economy is expanding
2H ago 
Virgin founder Richard Branson says the rich may need "heavy taxes"
If wealthy can't make capitalism work for more people, "we deserve to have very heavy taxes," philanthropist says
5H ago 
Amazon cancels New York City headquarters
E-commerce giant had faced fierce opposition for a planned New York location projected to cost $3 billion in incentives
updated 45M ago 
Romance scams break hearts and bust bank accounts
"I was just ready to be in love" — music to the ears of a swindler looking to con someone out of her cash
5H ago 
"Since Parkland" profiles 1,200 kids killed by guns
More than 200 teen reporters told the stories of young lives lost to bullets
updated 24M ago 
Persons of interest ID'd in alleged attack on "Empire" actor
The "Empire" actor gives a detailed account to "Good Morning America," says attack left him "forever changed"
3H ago 
Apple lawyer who oversaw insider trading policy charged with insider trading
Former attorney at the tech giant allegedly drew on non-public earnings information to cash in
Feb 13 
Gunman kills wife at dentist's office, gets shot by bystander
Armed bystander shoots gunman, detains him, waits for police to arrive, police say
Feb 13 
White supremacist gang in Arkansas accused of brutal tactics
Group called "reprehensible in its admiration for Nazi imagery and racist views, but even more alarming are the crimes and violence perpetrated by these defendants"
Feb 13 Original Article
