Open-Source Fire Science

Wildfire Models GridFire

GRID Fire Model

GridFire Wildfire Model

Developed by Dr. Gary Johnson and others at Spatial Informatics Group, GridFire is a next-generation wildfire modeling system designed to support dynamic, large-scale simulations of fire behavior under uncertain weather conditions. Developed to enhance operational planning and hazard forecasting in California and beyond, GridFire leverages probabilistic approaches and high-performance computing to produce realistic fire spread scenarios in both near-term (e.g., daily to weekly) and long-term (e.g., seasonal to decadal) timeframes.

At its core, GridFire integrates forecasted weather from observation or model and ignitions derived from historical patterns or user-defined scenarios. Fires are simulated as ensembles with hundreds of possible outcomes to capture uncertainty in ignition timing, location, and meteorological conditions. Outputs include fire perimeters, burn probabilities, and arrival times, offering detailed spatial and temporal insights into potential wildfire impacts.

GridFire KEY Capabilities

1

Probabilistic Ignition Modeling: Based on ignition likelihood surfaces derived from recent fire history and regional fire-weather conditions.

2

Ensemble Fire Spread Simulations: Hundreds of fire simulations per scenario using varying ignition points, weather trajectories, and fuel conditions.

3

Flexible Inputs: Accepts both forecast and historical weather, dynamic fuel moisture scenarios, and multiple land cover datasets.

4

Output Products: Includes probabilistic burn perimeters, time-to-arrival maps, and risk overlays to critical infrastructure or high-value resources.

Pyregence Github Repository

GridFire is part of the PyreCast ecosystem, supporting decision-makers in utility operations, emergency management, land-use planning, and climate adaptation. It is currently being refined for real-time deployment and integration with machine learning-based fire occurrence models and dynamic fuel forecasts.

Users can access GridFire from the Pyregence Github Repository.