Get ready for weather whiplash in Southern California this fall and winter

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What to expect: The latest outlook from the National Oceanic and Atmospheric Association predicts a 71% chance of La Niña conditions this fall. For Southern California, that global climate pattern historically has meant drier winters. But a warming planet is making rainfall, when it does come, more extreme. “We really do expect more of the same, which is big swings in our weather,” said Karla Nemeth, the director of the state’s Department of Water Resources.

Why it matters: Bigger swings between wet and dry weather make it harder to manage California’s water supply, push aging infrastructure to its limits and make fire seasons worse. For example, 2023 was a record-setting wet year here, despite La Niña, followed by another fairly wet year. All that led to a lot of vegetation growth that quickly dried out when, last winter, much of Southern California had the driest start to the wet season on record. That made the region a tinderbox ahead of January’s devastating fires.

The climate change connection: When we burn fossil fuels like coal, oil and methane gas, greenhouse gases are released into the atmosphere, which in turn heats up the planet. That heating leads to longer and hotter droughts, causing more water to evaporate into the atmosphere. That water eventually comes back down in the form of more intense storms.