Low (Green): Fuels do not ignite readily from small firebrands. A more intense heat source, such as lightning or matches, may start fires in duff or grasslands. Fires in cured grasslands may burn freely a few hours after rain; however, in woods and conifer stands, fires may spread slowly by creeping or smoldering. There is little danger of spot fires.
Moderate (Blue): Fires can start from most accidental causes, however, with the exception of lightning fires, the number of ignitions is generally low. Fires in open grassland or meadows will burn briskly and spread rapidly on windy days. Timber fires spread slowly to moderately fast. The average fire is of moderate intensity, although heavy concentrations of fuel may burn with more intensity. Short-distance spot fires may occur. Fires are generally not likely to become serious and control is relatively easy.
High (Yellow): All fine dead fuels start from most causes. Unattended brush and campfires are likely to escape. Fires spread rapidly and short-distance spot fires are common. High-intensity burning may develop on slopes or in concentrations of fine fuels. Fires may become serious and their control difficult. No open slash burning or large burn piles are allowed in Summit County when the wildfire danger is at HIGH or above. Recreational campfires (less than 3 feet in diameter and 2 feet high) are permitted unless there is a state or county burn ban in effect.
Very High (Orange): Fires start easily from all causes and immediately after ignition, spread rapidly and increase quickly in intensity. Spot fires are a constant danger. Crown fires may be present and move aggressively during a wind event. Fires burning in light fuels may quickly develop high intensity characteristics such as long-distance spot fires.
Extreme (Red): Fires start quickly, spread quickly, and burn with high intensely. All fires are potentially serious. Direct attack is rarely possible, and may be dangerous except immediately after ignition. Fires that develop headway in heavy slash, jackstraw, blowdown or in conifer stands may be unmanageable. Under these conditions, the only effective and safe control actions are on the flanks and heel of the fire. Extreme caution shall be utilized by all suppression personnel.
Reference: National Wildfire Coordinating Group, NFDRS system data and local factors