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Extreme Weather and Wildfire

  • Historical Analysis Map

The historical analysis map shows the locations of California’s eight fire regions and the extreme weather types associated with each.

Historical Analysis Map
This map shows the predominant extreme weather types (XWT) across regions in California (Prein et al. 2021, in submission to Journal of Geophysical Research: Atmospheres).

The arrows show the predominant low-level wind direction of each extreme weather type. The colors of the arrows indicate the dominant atmospheric process associated with the extreme weather type. The eight regions were defined based on fuel and fire weather conditions. No extreme weather types were derived for the Central Valley and the Desert Southwest because of their small sample size of observed fires. The Northern and Sierra regions are mainly forested. The central and southern coastal regions feature chaparral, grass-oak savanna, and urban areas. Fire ignition is mostly human-caused in urban regions, caused by dry lightning in the Northern and Modoc regions, and of mixed natural and human cause in the Sierra regions.

Extreme Weather Team
Historical Analysis

We analyzed the types of extreme weather associated with major fires in eight distinct regions across California.

We can now provide a way to make critical comparisons, with the ability to quantify the similarity of any given day’s weather to problematic historical conditions.