Executive Summary
The start of 2025 brought two devastating wildfires to Southern California: the Palisades Fire and the Eaton Fire, a tragic event that led to significant loss of life and property. These events, fueled by severe Santa Ana winds and abundant post–atmospheric river vegetation, left behind widespread destruction, including thousands of damaged and destroyed structures. They also reinforced a larger trend of increasingly volatile wildfire behavior in the region—an outcome of shifting climatic conditions, altered precipitation patterns, and extended fire seasons.
This volatility is underscored by data showing fire season peaks later in the year than previously observed, with frequent shifts in the El Niño–Southern Oscillation resulting in heavy rains that spur rapid fuel growth, followed by extreme dryness and high wind conditions. Consequently, traditional wildfire models have struggled to accurately capture the evolving nature of these risks.
In contrast, Delos Insurance’s wildfire model successfully anticipated the potential for catastrophic wildfires in the affected areas. The result of Delos’ underwriting success was zero wildfire losses on their portfolio of 25,000 insured properties in these events. Delos achieves this through a robust methodology that integrates high-resolution data on fuels, wind, and climate, augmented by advanced machine learning techniques that do not overly rely on past fire trends. Repeated back-testing and expert reviews further ensure the model’s accuracy and adaptability to changing wildfire conditions.
By combining advanced data analysis, machine learning, and in-depth domain expertise, Delos Insurance demonstrates how forward-thinking approaches can not only protect against existing risks but also stay ahead of evolving wildfire threats. The experience of the Palisades and Eaton Fires highlights the necessity for insurers, reinsurers, and other industry stakeholders to adopt innovative solutions to remain resilient in the face of increasingly unpredictable wildfires.
Introduction
The start of 2025 marked a tragic chapter in Southern California’s history as wildfires once again wreaked havoc across the region. This white paper focuses on two specific fires—the Palisades Fire and the Eaton Fire, which, together, scorched nearly 40,000 acres and resulted in extensive property damage and loss of life. Beyond their immediate devastation, these events shine a light on the evolving wildfire threats in Southern California, driven by shifting climate patterns, human development at the wildland-urban interface, and an increased prevalence of extreme weather events.
Though wildfires have long been part of the region’s ecological cycle, factors such as the El Niño–Southern Oscillation (ENSO), lengthening drought conditions, and extreme wind events have significantly altered fire behavior in recent years. As these elements converge, traditional models built on historical fire patterns are increasingly challenged, leaving both communities and insurers grappling with unpredictable risks.
In the following sections, this paper first provides an overview of the Palisades and Eaton Fires, detailing their timelines, spread, and impacts on local communities. Next, it explores the broader, shifting wildfire risk landscape in Southern California—outlining the climate, land-use, and ecological changes that have contributed to these severe events. Finally, the paper discusses how Delos Insurance’s advanced wildfire modeling approach has effectively identified these emergent risks, offering a fresh perspective on assessing and mitigating wildfire exposure. By examining these two fires in the context of broader regional shifts, we highlight the need for cutting-edge modeling solutions and underscore the importance of collaborative efforts to build resilience against the growing threat of wildfires.
Overview of the fires
Both fires ignited during an extreme Santa Ana wind event, with gusts reaching up to 100 mph. The fires quickly spread due to an abundance of vegetation fueled by heavy rainfall from the 2024 atmospheric river events. These conditions enabled the fires to rapidly encroach upon the wildland-urban interface (WUI) and trigger urban conflagrations. Suppression efforts were significantly hampered by the strong winds, which grounded air support, leaving ground crews to face immense challenges.
evolving wildfire risk in southern california
Wildfires have long been a natural part of Southern California's landscape. However, their frequency, severity, and behavior have shifted dramatically in recent years due to human activity and climate change, necessitating a reassessment of risk and mitigation strategies.
The El Niño-Southern Oscillation (ENSO), a key climate driver, has become increasingly frequent and severe due to climate change. This has amplified atmospheric river events like the Pineapple Express, which bring heavy rainfall but exacerbate wildfire risk by fostering rapid vegetation growth followed by prolonged dry periods. For example, the Palisades and Eaton Fires followed a strong El Niño event in late 2024 that transitioned abruptly into a La Niña phase, creating abundant vegetation during the rainy period and extreme dryness in the months leading up to the fires. Historically, Santa Ana winds were more likely to occur after the precipitation season had begun, mitigating their fire-spreading potential. However, as climate change has pushed the beginning of the precipitation season later and later in the year, these winds increasingly are occurring during drought conditions, and the resulting risk of large, destructive wildfires has grown significantly. Though wildfires have long been part of the region’s ecological cycle, factors such as the El Niño–Southern Oscillation (ENSO), lengthening drought conditions, and extreme wind events have significantly altered fire behavior in recent years. As these elements converge, traditional models built on historical fire patterns are increasingly challenged, leaving both communities and insurers grappling with unpredictable risks.
Adding to this challenge is the shifting fire behavior seen across decades. Data on maximum fire sizes by month reveals a troubling trend. From 1985 to 1999, fires peaked in July and diminished after August. Between 2000 and 2009, fire sizes began to show secondary peaks later in the year. Most recently, from 2010 onward, a pronounced secondary peak has emerged in October and December, signaling an extended fire season. This shift, combined with the proliferation of invasive plant species, declining forest health, and worsening climate conditions, has exposed previously low-risk areas to significant wildfire hazards. These evolving dynamics present challenges for models relying solely on historical fire patterns, further highlighting the need for advanced predictive approaches.
DELOS INSURANCE: A MODEL FOR WILDFIRE RISK ASSESSMENT
Despite having 25,000 policies across California, including areas that traditional models consider wildfire exposed, Delos experienced zero fire losses during the Palisades and Eaton Fires. The success of Delos’ wildfire model lies in its robust methodology. First, the model integrates high-resolution data on fuel, wind, climate, and fire behavior alongside hundreds of additional layers of supporting data, providing comprehensive insight into wildfire risks. Second, it employs advanced machine learning methodologies looking at wildfire behavior independent from historical events to ensure that there are no surprises from tail-end risk events like the Palisades and Eaton fires. Finally, the model undergoes rigorous back-testing against historical fires and is reviewed by wildfire experts to ensure both accuracy and reliability.
This innovative approach allows Delos to identify high-risk areas, such as those affected by the Palisades and Eaton Fires. At the same time, the model enables the company to insure properties in areas deemed high-risk by traditional models but which the Delos model identifies as safe. Since its inception in 2017, the Delos model has consistently demonstrated its effectiveness. It successfully predicted virtually every major fire event in California since then, including events that surprised the rest of the industry such as the Camp Fire, and has continued to successfully adapt to the evolving wildfire landscape.
conclusion
The Palisades and Eaton Fires serve as a stark reminder of the evolving wildfire risks in Southern California and the need for innovative solutions in wildfire risk mitigation. As climate change and environmental shifts continue to impact fire behavior, traditional models struggle to keep pace with emerging risks. Delos Insurance’s success in avoiding fire losses underscores the effectiveness of advanced wildfire modeling in identifying and mitigating exposure.
By leveraging cutting-edge data, expert analysis, and a deep understanding of wildfire behavior, Delos is positioned as a trusted partner for those seeking to navigate the growing complexities of wildfire risk. We invite reinsurers, insurers, partners, and industry stakeholders to connect with us to learn more about our model and how it can enhance risk assessment strategies. Together, we can build a more resilient future in the face of evolving wildfire threats.
