An analysis of the duration and severity of power outages during weather events across U.S. Counties

Power grids are increasingly vulnerable to weather events, which not only lead to power outages but also complicate analysis efforts to inform planning and mitigation strategies. While previous studies have focused on individual hazards or regions, comparative assessments across event types and geographic areas are limited. This study conducted a county-level, spatio-temporal analysis of power outages during weather events across the contiguous United States, utilizing an integrated dataset of historical outage and weather event records along with county-level environmental, infrastructural, and demographic features. We analyzed 124,291 historical weather events from November 2014 to November 2022 (categorized into 12 hazards and a co-occurring events category) to characterize outages by duration, severity, and correlations with local features. Our findings revealed that outage characteristics vary systematically by hazard, with tropical cyclones causing outages that are 5.4 times longer and 17.8 times more severe than the median for single-hazard events. Co-occurring events led to both increased outage duration and severity for almost 90% of paired hazards (compared to single-hazard events). An evaluation of local features identified multiple patterns in outage duration and severity. For example, across all hazards, highly developed areas generally experienced less severe but longer-lasting outages, while energy corridors were generally associated with more severe outages; affluence had an inverse relationship with both outage duration and severity. Hazard-specific patterns were also identified with local features, with outlying forested areas generally associated with longer and more severe outages, primarily during wind-based events. These insights provide a foundation for further assessments of power outages during weather events and can inform strategies to enhance grid resilience to weather events.