Observational networks enhance real‐time situational awareness for emergency and water resource management during extreme weather events. We present examples of how a diverse, multitiered observational network in California provided insights into hydrometeorological processes and impacts during a 3‐day atmospheric river storm centered on 14 February 2019. This network, which has been developed over the past two decades, aims to improve understanding and mitigation of effects from extreme storms influencing water resources and natural hazards. We combine atmospheric reanalysis output and additional observations to show how the network allows: (1) the validation of record cool season precipitable water observations over southern California; (2) the identification of phenomena that produce natural hazards and present difficulties for short‐term weather forecast models, such as extreme precipitation amounts and snow level variability; (3) the use of soil moisture data to improve hydrologic model forecast skill in northern California's Russian River basin; and (4) the combination of meteorological data with seismic observations to identify when a large avalanche occurred on Mount Shasta. This case study highlights the value of investments in diverse observational assets and the importance of continued support and synthesis of these networks to characterize climatological context and advance understanding of processes modulating extreme weather.

中文翻译：

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利用多种传感器网络观测极端大气河暴

观测网络增强了极端天气事件中紧急情况和水资源管理的实时态势感知。我们将举例说明加利福尼亚的一个多样化，多层的观测网络如何在以2019年2月14日为中心的3天大气河暴雨中提供有关水文气象过程和影响的见解。该网络在过去的二十年中得到了发展，旨在改善了解和缓解极端风暴对水资源和自然灾害的影响。我们将大气再分析输出和其他观测资料结合起来，以显示该网络如何实现：（1）验证南加州创纪录的冷季可降水量观测资料；（2）识别产生自然灾害并为短期天气预报模型带来困难的现象，例如极端降水量和雪位多变性；（3）利用土壤水分数据来提高北加利福尼亚州俄罗斯流域的水文模型预报技能；（4）将气象数据与地震观测资料结合起来，以识别沙斯塔山何时发生大雪崩。本案例研究强调了对各种观测资产的投资价值，以及持续支持和综合这些网络以表征气候背景并加深对调节极端天气过程的了解的重要性。（3）利用土壤水分数据来提高北加利福尼亚州俄罗斯流域的水文模型预报技能；（4）将气象数据与地震观测资料结合起来，以识别沙斯塔山何时发生大雪崩。本案例研究强调了对各种观测资产的投资价值，以及持续支持和综合这些网络以表征气候背景并加深对调节极端天气过程的了解的重要性。（3）利用土壤水分数据来提高北加利福尼亚州俄罗斯流域的水文模型预报技能；（4）将气象数据与地震观测资料结合起来，以识别沙斯塔山何时发生大雪崩。本案例研究强调了对各种观测资产的投资价值，以及持续支持和综合这些网络以表征气候背景并加深对调节极端天气过程的了解的重要性。