A sudden increase in fireline intensity or rate of spread of a fire sufficient to preclude direct control or to upset existing suppression plans This is often accompanied by violent convection
Sudden increase in fire intensity or rate of spread sufficient to preclude direct suppression or to upset existing suppression strategies Often accompanied by violent convection and may have other characteristics of a fire storm
Sudden increase in fire intensity or rate of spread sufficient to preclude direct control or to upset existing control plans Often accompanied by violent convection and may have other characteristics of a fire storm