COLUMBIA, Md. — UL Research Institutes’ Fire Safety Research Institute has released the “Southern California Fires Timeline Report,” the first of two reports in an independent analysis commissioned by the Office of the Governor of California.
The reports examine the series of devastating fires that swept Southern California between January 7 and 31, 2025, causing significant destruction across the region. During that period, large areas of Los Angeles County and southern Ventura County were impacted by rapidly evolving wildfires and two major conflagrations driven by extreme winds, low humidity and drought-stressed vegetation.
As of September 29, 2025, the fires had resulted in 32 confirmed fatalities, extensive property damage and widespread community disruption.
“Our report represents a critical first step in understanding how the Southern California fires last January progressed, and how agencies responded during this unprecedented event,” Vice President and Executive Director Steve Kerber said. “Documenting these preparedness measures and response activities across 12 simultaneous fires is essential for strengthening our defenses against wildfires that interface with the built environment.”
ULRI carried out an extensive data collection effort to build a detailed timeline and factual record of the Southern California fires. Researchers drew on a wide range of sources, including on-the-ground damage assessments, photos and videos, weather reports, radio recordings and transcripts, dispatch logs, resource requests and location data, as well as conversations with residents and technical discussions with personnel from multiple agencies and organizations.
Strong data points were consolidated into a mapping application to produce time lapse visualizations of fire activity for the Palisades and Eaton Fires. ULRI has made videos of these maps, along with a spreadsheet of the available timestamped data, available for review.
The timeline report will serve as the foundation for Phase Two, the Southern California Fires Incident Analysis Report. That analysis will examine conditions before the fires, how the built environment affected fire behavior, first responders’ actions and agency capabilities in managing urban conflagrations. It will also provide detailed recommendations to improve wildfire preparedness and response for the State of California, local officials and communities.
