Southern California is bracing for what could be one of its wettest Christmas holidays in decades as a powerful "Pineapple Express" atmospheric river barrels toward the region, threatening record-breaking rainfall, hazardous winds, and widespread travel disruptions. The National Weather Service and meteorologists across multiple agencies are sounding the alarm, urging residents and travelers alike to prepare for a week of wild weather, with the worst impacts expected from December 23 through December 25, 2025.
This storm system, drawing a deep plume of tropical moisture from Hawaii, is forecast to unleash several inches of rain across coastal and valley areas, with even heavier amounts in the foothills and mountains. According to FOX Weather and the Los Angeles Times, coastal and valley communities should expect 2 to 4 inches of rain, while mountainous regions may see as much as 8 to 10 inches by Christmas Day. The last time downtown Los Angeles saw 2 or more inches of rain over Christmas was back in 1971, and forecasters are giving an 80% chance of that threshold being met or exceeded this year.
The storm arrives in a series of waves, with the first round of moisture targeting Northern California and the Bay Area from December 20 to 22. The main event for Southern California begins Tuesday, December 23, with light showers developing along the coast and intensifying overnight. The peak is expected to hit on Christmas Eve, December 24, bringing drenching downpours, the highest risk of urban flooding, and possible mudslides, especially in areas scarred by recent wildfires. Lighter showers are forecast to linger through Christmas Day, as the system gradually moves eastward.
For those planning holiday travel, the timing couldn’t be worse. AAA projects that over 10 million people will be journeying through Southern California during the holiday week—a 2% increase from last year. Major highways including I-5, I-10, I-15, Highway 101, and I-40 are expected to see treacherous conditions, with the risk of road accidents heightened by slick pavement and reduced visibility. Air travelers aren’t spared either: Los Angeles International, San Diego International, San Francisco International, and Sacramento International airports are all bracing for delays and cancellations as the weather deteriorates. “Anyone with holiday travel plans by road and by air should keep an eye on the forecast and adjust accordingly,” the National Weather Service warned in an online forecast.
Alex Sosnowski, a senior meteorologist at AccuWeather, cautioned that “drenching downpours and urban flooding problems are predicted to occur in the Los Angeles and San Diego metro areas from Wednesday Dec. 24 to Friday Dec. 26, which may spoil outdoor Christmas-related activities.” The National Weather Service in Los Angeles put it simply: “Start to mentally prepare for a wet Christmas holiday.”
The potential severity of this storm is underscored by the rainfall probabilities being tracked by meteorologists. According to the Los Angeles Times, there’s a 40% chance of “very high” rainfall—meaning 4 or more inches—along the coasts and valleys of Los Angeles, Ventura, and southern Santa Barbara counties, and an 8-inch or greater deluge in the mountains and foothills. Even the so-called "high amounts" scenario, with 2 to 4 inches in the lowlands and 4 to 8 inches in the mountains, carries significant risks: flooded freeway lanes, localized flooding into homes and businesses, and the potential for swiftwater rescues in fast-moving rivers and streams.
Communities across Orange County, the Inland Empire, and San Diego County are also on alert. Light showers may begin as early as Tuesday, but the heaviest rainfall is expected on Wednesday, December 24, with flood and mudslide threats continuing into Christmas Day. The High Desert could see 2 to 3 inches of rain, while the mountains may be pummeled with the highest totals. The National Weather Service’s Oxnard office is warning of peak rainfall rates between half an inch and one inch per hour from midnight Tuesday through noon Wednesday—intensity that greatly increases the risk of flash flooding and debris flows, especially in areas with recent burn scars.
The parade of storms doesn’t just bring rain. Powerful winds are another concern, with gusts from the south potentially toppling trees and power lines. On Tuesday night, Los Angeles could see peak gusts of 31 mph, Woodland Hills 38 mph, Paso Robles 52 mph, and San Luis Obispo 53 mph. There’s a 65% chance of gusts exceeding 35 mph in Huntington Beach and a 60% chance in San Diego, according to the weather service. Residents are advised to avoid parking under trees and to secure loose outdoor objects to prevent damage.
Flood watches have already been issued for most of Northern California, where the atmospheric river will first make landfall. The region is forecast to receive 3 to 5 inches of rain, with the northern Sierra Nevada foothills possibly seeing up to 10 inches by Tuesday, December 23. Flash flooding threats are considered moderate (Level 3 of 4) in Northern California and slight (Level 2 of 4) in major cities like San Francisco and Sacramento. Debris flows in recent burn scars are a distinct possibility, and river flooding is expected to be more widespread, especially near the California coast.
There’s a silver lining for mountain communities and ski resorts: the snow-starved Sierra Nevada is finally projected to receive a much-needed blanket of snow, with snow levels dropping to 5,000–6,000 feet by Christmas Eve. While this will create dangerous travel conditions through mountain passes, it’s a welcome relief for the region’s water supply and winter recreation industry. Heavy snow is also likely to spill into parts of the Rockies as the moisture-laden system pushes eastward.
Officials are urging Californians to take proactive steps to minimize the risk to life and property. Recommendations include clearing leaves and debris from rain gutters and storm drains, securing outdoor decorations and trash bin lids, checking flight statuses frequently, slowing down and increasing following distances when driving, and signing up for local emergency alerts to receive timely updates about flash flood warnings or evacuation orders. “Avoid parking under trees,” the weather service advised, and “secure loose outdoor objects.”
Despite the daunting forecast, the holiday spirit appears undeterred. The surge in travel numbers suggests that many are determined to reach loved ones, rain or shine. But with the potential for significant mudslides, flooded freeways, overflowing streams and rivers, coastal flooding, downed trees and power lines, and dangerous sea conditions, officials stress that preparation and vigilance will be key to staying safe this Christmas.
As the Pineapple Express barrels toward California, residents are reminded that nature doesn’t always check the calendar. This year, the state’s Christmas plans may be washed in more ways than one, offering a dramatic reminder of the power and unpredictability of the West Coast’s winter weather.
