大气河流横扫南加州，多地11月15日单日降雨量打破保持70多年的纪录
2025年11月15日，一条大气河流横扫美国加利福尼亚州南部，洛杉矶县、Ventura县、Santa Barbara县等多地降下暴雨。美国气象预测中心当天对南加州发布过量降雨「中等风险」评级，范围扩大到整个橙县和圣迭戈县最北端；国家气象局洛杉矶／Oxnard办公室的洪水观察覆盖Santa Barbara县大部、Ventura县、洛杉矶县和近海岛屿，有效至当晚，雷雨附近和向南山坡的降雨强度可达每小时约1英寸。
当天上午9时39分，国家气象局对洛杉矶县中部的伊顿大火过火区及周边发布山洪警报，有效至中午：雷达和自动雨量计显示过火区上空雨势加强，预计降雨强度每小时0.5到1英寸，山洪和泥石流正在发生或即将开始，威胁等级为「相当严重」。受影响地点包括Mount Wilson、Pasadena、Altadena、Sierra Madre、Arcadia和Monrovia。气象局说，过火区的泥石流可由岩石、泥土和植被等松散物组成，会冲击沟渠、道路和火烧区下方的住宅。
这场风暴由近海一个强闭合低压系统引导，把与热带相连的丰沛水汽带以大气河流的形式送进南加州。气象预测中心说，当天上午圣莫尼卡山脉一带15分钟降雨量达到0.5到0.75英寸，南加州沿海雷暴的最大降雨强度可达每小时1英寸；横断山脉一带到次日清晨预计再增3到5英寸降雨，其他地区预计1到2英寸、局部3英寸。
国家气象局的事后统计显示，11月15日当天多座气象站打破单日降雨纪录：洛杉矶市中心1.65英寸，打破1952年1.64英寸的旧纪录；Long Beach机场1.34英寸，打破1965年0.74英寸的旧纪录；Burbank机场1.71英寸，打破1952年1.62英寸的旧纪录；加州大学洛杉矶分校1.72英寸，打破1952年1.10英寸的旧纪录；Oxnard的国家气象局站点3.18英寸，打破1934年1.80英寸的旧纪录；Santa Barbara机场2.90英寸，打破1952年1.92英寸的旧纪录；Sandberg2.46英寸、Camarillo机场2.78英寸，同样刷新各自站点的当日纪录。
Atmospheric River Soaks Southern California as November 15 Daily Rainfall Records Fall Across the Region
On November 15, 2025, an atmospheric river swept across Southern California, bringing heavy rain to Los Angeles, Ventura and Santa Barbara Counties. The Weather Prediction Center placed Southern California under a Moderate Risk of excessive rainfall that day, expanding the risk area to all of Orange County and far northern San Diego County. A flood watch from the National Weather Service office in Los Angeles/Oxnard covered most of Santa Barbara County, Ventura County, Los Angeles County and the offshore islands through the evening, with rainfall rates up to about one inch per hour possible near thunderstorms and on south-facing foothills and mountains.
At 9:39 a.m., the National Weather Service issued a flash flood warning for the Eaton burn scar and vicinity in central Los Angeles County, in effect until noon: Doppler radar and automated rain gauges indicated heavy rain intensifying over the burn scar, with an expected rainfall rate of 0.5 to 1 inch per hour, and flash flooding and debris flows ongoing or expected to begin shortly, at a "considerable" damage threat level. Locations facing flash flooding included Mount Wilson, Pasadena, Altadena, Sierra Madre, Arcadia and Monrovia. The weather service said debris flows from the burn scar, made up of rock, mud, vegetation and other loose material, would impact drainages, roads and residences in and directly below the burn area.
The storm was driven by a strong closed low offshore that drew a plume of tropical moisture into Southern California in the form of an atmospheric river. The Weather Prediction Center said 15-minute rainfall totals of 0.5 to 0.75 inches were observed in the Santa Monica Mountains that morning, that thunderstorms along the Southern California coast could produce maximum rainfall rates of one inch per hour, and that the Transverse Ranges were expected to receive an additional 3 to 5 inches of rain through Sunday morning, with 1 to 2 inches, locally 3 inches, elsewhere.
National Weather Service tallies later showed that numerous stations set daily rainfall records on November 15: downtown Los Angeles recorded 1.65 inches, breaking the old record of 1.64 inches set in 1952; Long Beach Airport recorded 1.34 inches, breaking the 1965 record of 0.74 inches; Burbank Airport recorded 1.71 inches, breaking the 1952 record of 1.62 inches; UCLA recorded 1.72 inches, breaking the 1952 record of 1.10 inches; the National Weather Service station in Oxnard recorded 3.18 inches, breaking the 1934 record of 1.80 inches; Santa Barbara Airport recorded 2.90 inches, breaking the 1952 record of 1.92 inches; and Sandberg, with 2.46 inches, and Camarillo Airport, with 2.78 inches, also set new daily records for their stations.
来源：美国国家气象局
发布：GSM·美国（发布链接）
图片来源：图：2025年11月一条大气河流逼近美国西海岸的GOES卫星水汽图（资料图）。GOES影像由科罗拉多州立大学大气研究合作研究所与美国国家海洋和大气管理局提供，公共领域，经Wikimedia Commons。 / Photo: A GOES satellite water-vapor image of an atmospheric river approaching the U.S. West Coast in November 2025 (file image). GOES imagery by CSU/CIRA and NOAA, public domain, via Wikimedia Commons.
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