(KTLA) – El Niño is here, but can you tell?
California, which tends to see more rain during an El Niño year, hasn’t seen a huge impact – at least not yet. Joe Sirard, a meteorologist with the National Weather Service office in Los Angeles, said precipitation for the current water year is generally lagging behind averages.
“Los Angeles, San Diego and San Francisco are all below normal in rainfall,” Sirard told Nexstar’s KTLA on Monday.
El Niño is the warming of surface water temperatures along the equator, which can impact the broad weather patterns we see on land. California – especially the southern half of the state – tends to see more rain during an El Niño year, as do southern and Gulf states. Meanwhile, the Pacific Northwest and Ohio Valley tend be drier than usual.
But nothing is guaranteed with El Niño, explained Michelle L’Heureux, a scientist at the Climate Prediction Center. We’re always speaking in terms of probabilities.
Take a look at the latest seasonal outlook released in December, for example. The government’s climatologists said there is a slight chance of above-normal moisture for California through March. The chances are stronger in the Gulf. Both the Pacific Northwest and Ohio Valley are leaning toward a drier-than-average season.
All those probabilities are consistent with El Niño patterns – but even still, they are just favored forecasts, not set-in-stone outcomes.
L’Heureux explained that according to the seasonal forecast (above), California is just slightly favored to have a wetter-than-average winter. Even if California has a 40% chance of seeing above-average rainfall, that means it has a 60% chance of the other two possibilities (average rainfall or below-average rainfall) combined.
Above-average rainfall is still the most likely outcome of the three, but it’s far from a sure thing.
Sirard said the state hasn’t seen above-average precipitation yet, except in isolated areas. In the current water year, which started on Oct. 1, 2023, and runs through Sept. 30, 2024, downtown Los Angeles has received 3.18 inches of rain, which is 79% of the average, according to the National Oceanic and Atmospheric Administration (NOAA). San Francisco has seen 5.51 inches of rain, or 75% of average. San Diego is below 50%.
At this point in 2023, California was well on its way to one of its wettest and snowiest water years on record as one atmospheric river after another drenched the state with torrential rain and buried the mountains under historic levels of snow.
Sirard said California is currently seeing a northwestern air flow that is bringing cooler temperatures but very little precipitation, and the short-term outlook shows no significant change.
That illustrates another point: El Niño isn’t all-powerful. Other factors, like rising global temperatures or “random weather chaos” (as L’Heureux described it) are still at play.
“El Niño nudges weather patterns in certain directions, but is not always strong enough to leave its mark everywhere,” she said.
“Obviously there are some recent weather events that seem to suggest having an El Niño flavor – for instance the repeated storms over the southeastern and eastern U.S.,” L’Heureux said. “But it’s still too soon to say whether the entire winter season is consistent with the El Niño pattern for the United States.”
Elsewhere in the world, the signs are more obvious. Australia and the Amazon saw dry El Niño-driven seasons, L’Heureux said, while the Horn of Africa saw increased rainfall. “So this strong El Niño is undoubtedly having an influence across the globe.”
As for California, Sirard said there is still plenty of time for El Niño to deliver.
“We don’t have a big moisture feed, like an atmospheric river, coming into our area right now,” said Sirard. “But the pattern will likely fluctuate and all it takes is one week of heavy rain to put us above normal.”