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.
Wildland Fire Update (27 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.
Fig.3. Geographic areas and coordination centers
(modified map from National Interagency Fire Center (NIFC)).
Wildland fire activity decreased in the southern and eastern due to increased precipitation. Very high to extreme fire conditions remain, however, in Texas, New Mexico and Arizona.
While burning conditions in some states are severe, other states throughout the country are experiencing ideal conditions for prescribed fires. As of today, nearly 430,000 acres (174,014 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, 29 March 2000
(Source: Florida Division of Forestry)
The Florida Forest Fire Weather Index (FWI) System is part of the “Florida Fire Management Information System (FFMIS)” and 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 28 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, 28 March 2000
(Source: Florida Forest Fire Weather Index (FWI) System)
Southern Area Coordination Center (GA-SAC): A total of 8 crews are being mobilized to fires in the area. Some overhead orders are filled.
The Fort Worth, Texas area had 2 tornados that caused severe damage in the downtown area. Softball size hail broke windows in skyscraper buildings in the downtown area and due to this, the downtown area is closed. At this time, there are 4 fatalities and 100+ injured. They are assessing the damage at this time. A tornado watch is still in affect for parts of northern Texas and southern Oklahoma. A storm is expected to move into Alabama, Georgia and the Carolinas tomorrow.
Southeastern and South Central Compact: No fire activity reported.
Arkansas/Oklahoma Interagency Coordination Center (AR-AOC): Heavy rainfall and severe thunderstorms spread across most of the state. The Center mobilized several crews and miscellaneous overhead to support the fires in North Carolina.
Eastern Oklahoma Region (OK-MAA): A prescribed burn was completed.
Buffalo National River (AR-BUP): The Park completed a prescribed burn.
Arkansas Forestry Commission (AR-ARS): The State had fire activity totaling 971 acres (393 ha).
Ouachita National Forest (AR-OUF): The Forest completed prescribed burning amounting to 11,423 acres (4,623 ha) .
Ozark & St. Francis National Forests (AR-OZF): The Wrong Way Fire of 160 acres (65 ha) is 100% controlled. The fire was lightning caused and burned for a couple of days prior to detection. One retardant drop was completed on the fire yesterday. Current threats are to commercial timber and the local watershed. Steep rocky terrain and low relative humidity caused control problems for the fire. The Forest completed prescribed burning.
Florida Interagency Coordination Center (FL-FIC): The weather forecast called for no chance of rain ,winds at 12 mph (19 km/h) and low humidity.
Big Cypress National Park (FL-BCP): The Park assisted the Florida Division of Forestry with a fire on 3/27. The Park completed a prescribed burn.
Florida Division of Forestry (FL-FLS): The State had fire activity.
National Forests in Florida (FL-FNF): The Forests reported fire activity. Two fires were from unknown causes, 2 fires from lightning and 2 fires were man-made.
Georgia Forestry Commission (GA-GAS): The State had 22 wildfires.
Chattahoochee-Oconee National Forest (GA-CHF): The Forest reported wildfire activity.
Kentucky Interagency Coordination Center (KY-KIC): A trace of precipitation was reported across central and northeast Kentucky yesterday. The state had high winds with gusting to 50-60 mph (80-96 km/h).
Kentucky Division of Forestry (KY-KYS): The state had fire activity on 3/27. One fire in the Northeast District was started from lightning and 1 fire in Breathitt County was started from a burned stolen vehicle.
Daniel Boone National Forest (KY-DBF): Yesterday the Asheville Hotshots were assigned to the Duck Run prescribed burn. Yesterday this burn was stated as a fire instead of a prescribed burn. The Stearns Ranger District will be completing a prescribed burn today. The District had a 5 acre (2 ha) fire started from a downed powerline.
Louisiana Interagency Coordination Center (LA-LIC): The State has modified their burning ban to allow some prescribed burning.
Louisiana Office of Forestry (LA-LAS): The State had fire activity amounting to 205 acres (83 ha).
National Forests in Mississippi (MS-MNF): On 3/24 the Desoto had a fire of 1,550 acres and as of 3/25 it was confined. The fire was started due to a military firing. The fire burned within the Camp Shelby Impact Area.
North Carolina Division of Forest Resources (NF-NCS): The State had fire activity on Monday.
National Forests in North Carolina (NC-NCF): The Forests reported 2 fires that started around 1400 yesterday. The fires are still active. The Franks Creek fire was approximately 100 acres+ (40 ha) and 3 air tankers were dropping retardant. The Asheville hotshots are committed to this fire along with 10 miscellaneous overhead. In addition, 3 Type II crews will arrive today. This fire is threatening 5 homes and has 4 structural fire departments protecting the homes. The Bent Creek fire was approximately 75+ acres (30 ha). There were 4 engines, 1 type II crew and 30 miscellaneous overhead on the fire. Three Type II crews will arrive today. This 104 acre (42 ha) fire is threatening a 50 year old experimental site. The fire destroyed 2 plots. No retardant drops were made due to extreme winds.
South Carolina Forestry Commission (SC-SCS): The State had fire activity.
Tennessee Division of Forestry (TN-TNS): The State had fire activity amounting to 168 acres (68 ha) on 3/27. The conditions on the fires were hazardous due to the high winds.
Virginia Interagency Coordination Center (VA-VIC): The Center supplied North Carolina with a Type II crew.
George Washington & Jefferson National Forests (VA-VAS): The Forests had some fire activity.
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.