The Wildland Fire Assessment System (WFAS) is a contribution of “The Fire Behavior Research Work Unit”, Missoula (Montana USA). The broad area component of the Wildland Fire Assessment System (WFAS) generates maps of selected fire weather and fire danger components. Fire Danger (Potential) is a normalized adjective rating class across different fuel models and station locations. It is based on information provided by local station managers about the primary fuel model, fire danger index selected to reflect staffing level, and climatological class breakpoints. Low danger (class 1) is green and extreme potential (class 5) is red.
Several active fire signals were recorded by NOAA/OSEI with the NOAA-14 POES AVHRR HRPT satellite on 24 March 2000 in the southeastern US.
Fig.3. Heat signatures and smoke plumes from a few areas of fire burning along the Georgia / Alabama border. Some of these may be controlled burns.
Wildland Fire Update (17 March 2000)
The National Interagency Fire Center (NIFC) provides new data of the current wildland fire season in the United States. These data were analysed after different geographic regions. Further, a five-year wildland fire comparison statistic shows the number and the area of wildland fires from 1996 to 2000.
Although wildland fire activity decreased during the past week, extreme fire conditions remain in California, Arizona, New Mexico, Texas, Illinois, and Virginia. In the first 77 days of 2000, over 0.5 million acres ( 202,343 ha) have been affected by wildland fires. This figure is nearly three times greater than the four-year average of 185,000 acres (74,867 ha) burned by this time of the year.
While burning conditions in some states are severe, other states throughout the country are experiencing ideal conditions for prescribed fires. As of today, nearly 400,000 acres (161,874 ha) of wildlands have been treated by prescription fires. Prescribed fires are planned under specified conditions intended to improve the health of the natural landscape and/or reduce hazardous build-up of vegetation that lead to devastating wildland fires.
Long-range, 30-day weather forecasts are predicting above-normal temperatures and below-normal precipitation for the southern tier of states from southern California to Florida and throughout the Midwest (see Fig.4. 30 and 90-day forecast maps).
Keetch-Byram Drought Index (KBDI) by Florida’s Division of Forestry / Forest Protection Bureau
John Keetch and George Byram developed the K/B index at the Southern Forest Fire Laboratory to evaluate the effects of long-term drying on litter and duff and subsequently, on fire activity (1968). The index is based on a measurement of 8 inches (20 cm) of available moisture in the upper soil layers that can be used by vegetation for evapotranspiration. The index measure is in hundredths (0.01) of an inch of water and has a range of 0 through 800, with 0 being saturated and 800 representing the worst drought condition. The index indicates deficit inches of available water in the soil. A K/B reading of 250 means there is a deficit of 2.5 inches (64 mm) of ground water available to the vegetation. As drought progresses, there is more available fuel that can contribute to fire intensity.
For further information on the KBDI please refer to Keetch-Byram Drought Index Revisited: Prescribed Fire Applications.
Fig.5. Keetch-Byram Drought Index Map of Florida, 26 March 2000
(Source: Florida Division of Forestry)
The Florida Forest Fire Weather Index (FWI) System consists of six components that account for the effects of fuel moisture and wind on fire behavior. The first three components are fuel moisture codes that follow daily changes in the moisture contents of three classes of forest fuel with different drying rates. The last three components are fire behavior indexes, representing rate of spread, amount of available fuel, and fire intensity; their values increase as fire weather severity increases. For detailed information on the Florida Fire Management Information System (FFMIS) the GFMC would like to refer to the original website.
According to the FFMIS for 24 March these parameters show various fire weather conditions for Florida.
Fine Fuel Moisture Code
Duff Moisture Code
Initial Spread Index
Fire Weather Index
Fig.6.-11. Output maps of the FFMIS, 24 March 2000
(Source: Florida Forest Fire Weather Index (FWI) System)
The weather forecast is predicting thunderstorms, high humidity and a warming trend along the Gulf Coast. Hail, strong winds, frequent lightning and heavy downpours can be expected with some of these storms. The I-10 corridor from Florida to Texas is in the worst of the drought, allowing for many brush fires to flare. A second batch of strong storms will develop in eastern Oklahoma, northeast Texas and Arkansas this afternoon.
Southeastern and South Central Compact: No fire activity reported.
Arkansas/Oklahoma Interagency Coordination Center (AR-AOC): A stationary front will continue from Memphis to Fort Smith area. Eastern and Central Arkansas was under a severe thunderstorm watch from1400-2000 hours.
Eastern Oklahoma Region (OK-MAA): The Okmulgee Office completed prescribed burning
Southern Plains Region (OK-AAA): The Concho Agency completed prescribed burning.
Ouachita National Forest (AR-OUF): The Forest completed prescribed burning.
Georgia Interagency Coordination Center (GA-GIC): The area has received no precipitation.
Georgia Forestry Commission (GA-GAS): The State had fire activity.
Chattahoochee-Oconee National Forest (GA-CHF): The Forest reported fire activity.
Kentucky Interagency Coordination Center (KY-KIC): The state received scattered showers, which did not lower the fire danger. The
temperatures are expected to be 70 degrees (21°C) and relative humidity 25-30%.
Daniel Boone National Forest (KY-DBF): The Forest received fire activity. The Am. Hollow Fire increased by 5 acres (2 ha). A helicopter flew for over 3 hours and dropped 4,536 gallons (17,170 liters) of water. The Forest is near RED FLAG conditions today.
Louisiana Interagency Coordination Center (LA-LIC): The State has modified their burning ban to allow some prescribed burning.
North Carolina Interagency Coordination Center (NC-NCC): The Area is expecting temperatures in the mid to high 70s (25°C) with humidity in the low 20s. The weather forecast is expecting initial activity to increase.
National Forests in North Carolina (NC-NCF): The Asheville Hotshots (Type I) and a State Bridge Crew (Type II) are committed to the Dicks Creek Fire on the Wayah Ranger District. The fire is 90+ acres (36 ha). It is a joint fire with North Carolina State. Helicopter 206HE is on this fire and they anticipate requesting another. The Douglas Fire has a Schenck Job Corp Crew (Type II) staffing this 20-25 acre (9-10 ha)fire. Three loads of retardant were dropped on the fires.
South Carolina Interagency Coordination Center (SC-SCC): Prescribed fire will continue today in the Piedmont and Coastal areas. The temperatures have been in the 70 degrees (21-26°C). Weather will continue to be warm and dry with a chance of showers on Monday.
Fort Jackson Army Training Center (SC-FJQ): The department completed a prescribed burn.
South Carolina Forestry Commission (SC-SCS): Helicopter 16EA completed 1,502 acres (607 ha) of aerial ignition at Fort Jackson.
Francis Marion & Sumter National Forests (SC-FMF): The Forests had fire activity and completed a prescribed burn.
Tennessee Interagency Coordination Center (TN-TNC): Four tanker drops were completed in North Carolina.
Cherokee National Forest (TN-CNF): The Forest completed one prescribed burn and had fire activity.
George Washington & Jefferson National Forests (VA-VAF): The Almira Fire on the Clinch Ranger district has staffed a fire of 7 acres (3 ha).
According to the Incident Management Situation Report three categories of fires are distinguished, such as:
2. Prescribed Fires
3. Wildland Fire Use Fires**
* This classification corresponds to the category “wildland fires” as defined by the National Interagency Fire Center (NIFC)
** A brief excursion to wildland fire terminology:
Wildland Fires: Fires occurring on any tpye of vegetation, regardless of ignition sources, damages or benefits. Wildfire: Any uncontrolled wildland fire which (1) may require suppression response, or (2) any uncontrolled wildland fire which meets management objectives and is declared as a Wildland Fire Use Fire (see below) or syn. Prescribed Natural Fire or Prescribed Fire. Prescribed Fire: Occasionally also called management-ignited fire, or prescribed burning, is a controlled application of fire to vegetation in either their natural or modified state, under specified environmental conditions which allow the fire to be confined to a predetermined area and at the same time to produce the intensity of heat and rate of spread required to attain planned resource management objectives. Wildland Fire Use Fire: Naturally ignited fire which is managed to achieve resource benefits under close supervision (syn. Prescribed Natural Fire)
Incident Management Situation Report (24 March 2000):
No new large fires were reported to the National Interagency Coordination Center this week. Initial attack activity has been light in the Southern, Eastern, Southwest, and Southern California Areas. Very high to extreme fire indices were reported in Texas, New Mexico, and Arizona. Outlook:
Arizona will be partly cloudy this weekend with high temperatures in the 50’s (10-15°C) in the north and 70’s (21-26°C) in the south. The rest of the week will be windy and cooler with a chance of valley showers or mountain snow. Temperatures will be in the 30’s (-1 to 4°C) in the mountains and 60’s (16-20°C) elsewhere.
Texas will be partly cloudy with patchy morning drizzle in the southwest. Tuesday and Wednesday will be breezy and cloudy with a chance of showers in the south. The remainder of the week will see a return to more normal conditions.
Florida will be partly cloudy this weekend with high temperatures in the 70’s (21-26°C) in the north and 80’s (27-31°C) south. Monday and Tuesday the forecast is for a chance of thunderstorms in the north and a slight chance of showers in the south. Wednesday will see a return to normal daily temperatures with little or no precipitation anticipated for the area.
Tab.2. Fires and area burnt year-to-date (24 March 2000)
(Source: Incident Management Situation Report)
At this time of the year prescribed burning operations are conducted routinely.
Fire is an important natural tool for ecosystem management. It can reduce dense vegetation improving wildlife habitat and lessening the potential for large, wildfire disasters. Land managers are directed to prepare a prescribed fire/burn plan for every area of public land that can burn. Some areas require total suppression while others will benefit from a wildland fire. Those areas that will benefit from a fire can be treated by a prescribed fire.
Especially, for the moment, in the southern and southeastern regions of the United States prescribed fire activities will be carried out in the following weeks and months. In this case, fire signals on satellite images can be traced back to this kind of land management activities.
In the Prescribed Fire Position Paper of the Forest Protection Bureau by the Division of Forestry in Florida, prescribed fire activity is described as a land management application that is essential to the practice of forestry, management of wildlife, preservation of endangered plant and animal species, improvement of range conditions and reduction of wildfire damage in the wildland/urban interface areas. While there is general public and landowner concern with increased smoke, reduced air quality, and liability; the general public and landowners benefit significantly from the reduction of devastating wildfire, improved wildlife habitat and forage, preservation of endangered and threatened plant and animal species, and improved management of forest resources. The prospect of severe reductions in the utilization of this management tool is of major concern to Florida’s natural resource managers and conservationists due to the subsequent loss of derived public and private benefits. They suggest the need for legislative attention.