A fire weather warning is a forecast advisory issued by the U.S. National Weather Service to assist land management and fire-fighting agencies in the day-to-day assessment of fire danger. The warning includes current fuel moisture and critical weather conditions that can lead to or increase the probability of wildfire activity.
Each National Weather Service in every state issues a different fire weather warning forecast. Also called a red flag warning, the forecast is affected by the region's topography, local vegetation type and distance from water sources. When the National Weather Service releases a red flag warning, the public is warned about the high fire danger and the increased probability of a quick-spreading fire in the local vegetation within 24 to 48 hours.