Data Methods: Fire Weather

The steps below describe how the values shown in the tool were calculated, from raw climate model output to the final data product.

Input data

Description: Ensemble of 4 bias-adjusted climate model simulations, dynamically downscaled using the WRF model for the state of California: EC-Earth3-r1i1p1f1, MPI-ESM1-2-HR-r3i1p1f1, TaiESM1-r1i1p1f1, MIROC6-r1i1p1f1.
Variables: Air temperature, water vapor mixing ratio, surface pressure, west-east and north-south wind components
Spatial resolution: 3 kilometers
Temporal resolution: Hourly
Time period: 1980-2100: the modeled historical period (1980-2014), followed by the SSP3-7.0 scenario (2015-2100)
Download: Browse in the Cal-Adapt data catalog (STAC), or download directly from cloud storage (AWS).

Description: The average number of days per year with a Fosberg fire weather index (FFWI) value of 50 or higher, and the change from the historical baseline. Values are given at each grid cell for each global warming level, as the mean, minimum, and maximum across simulations.
Shown in: Climate Metrics Map
Format: Zarr stores at 3 kilometer resolution
Download: Browse in the Cal-Adapt data catalog (STAC), or download directly from cloud storage (AWS).

For attribution, please cite this work as:

Cal-Adapt. (2026). Data Methods: Fire Weather. Cal-Adapt. https://cal-adapt.org/dashboard/data-methods/fire-weather