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.
The Keetch-Byram Drought Index (KBDI) is a soil/duff drought index that ranges from 0 (no drought) to 800 (extreme drought) and is based on a soil capacity of 8 inches of water. Factors in the index are maximum daily temperature, daily precipitation, antecedent precipitation, and annual precipitation. KBDI = 0 – 200: Soil moisture and large class fuel moistures are high and do not contribute much to fire intensity. Typical of spring dormant season following winter precipitation. KBDI = 200 – 400: Typical of late spring, early growing season. Lower litter and duff layers are drying and beginning to contribute to fire intensity. KBDI = 400 – 600: Typical of late summer, early fall. Lower litter and duff layers actively contribute to fire intensity and will burn actively. KBDI = 600 – 800: Often associated with more severe drought with increased wildfire occurrence. Intense, deep burning fires with significant downwind spotting can be expected. Live fuels can also be expected to burn actively at these levels.
For further information on the Keetch-Byram Drought Index (KBDI) by Florida’s Division of Forestry / Forest Protection Bureau please refer to Keetch-Byram Drought Index Revisited: Prescribed Fire Applications.
Several active fire signals were recorded by NOAA/OSEI with the NOAA-15 AVHRR satellite.
Fig.4. NOAA-15 POES AVHRR satellite image 13 June 2000.
Two heat signatures (red) are visible from fires burning in Colorado.
The Bobcat fire is burning about 12 miles west of Loveland, Colorado.
The High Meadow Fire is located southwest of Denver and has burned an estimated 1800 acres.
Fig.5. NOAA-15 POES AVHRR satellite image 13 June 2000.
Heat signatures are visible from a number of fires burning in eastern Oklahoma and Kansas.
According to the Fire and Aviation Management Morning Report (13 June 2000), current wildfires are burning in: New Mexico VIVEASH: This 28,283 acre (11,445 ha) fire is burning on the Santa Fe National Forest, five miles northwest of Pecos, New Mexico. 80% of the work has been done to contain the fire. There are 292 people working on the fire.
MAGDALENA: This is a complex of 21 fires burning on the Cibola National Forest, west of Socorro, New Mexico. The fires cover a total of 1,725 acres (698 ha). One new fire was reported yesterday. 99% of the work has been completed to contain these fires. There are 163 people working on the fires. Arizona OUTLET: This 14,118 acre (5713 ha) fire is burning at Grand Canyon National Park lands, 25 miles south of Jacob Lake, Arizona. 90% of the work has been completed to contain this fire. There are 328 people working on the fire. Florida BRIGHT HOUR: This 1,100 acre (445 ha) fire is burning on Florida State Division of Forestry administered land in Desoto County. 80% of the work to contain the fire is completed. There are 9 people working on the fire.
MICROWAVE: This 1,500 acre (607) fire is burning on lands protected by the Florida State Division of Forestry in Osceola County. 90% of the work has been done toward containment. There are 14 people working on the fire.
DC COMMAND: This 1,000 acre (404 ha) fire is burning on Florida State Division of Forestry managed land near Homestead, Florida. There are 5 people working on the fire. 50% of the work has been completed for containment.
SHIP COMMAND: This 625 acre (253 ha) fire is burning on Florida State Division of Forestry managed lands in Hillsborough County. There are 37 people working on this fire and 80% of the work has been completed for containment.
LOUISE: This 4,000 acre (1,618 ha) fire is burning on Florida State Division of Forestry administered land in Alachua County near Gainesville, Florida. 60 people are working on this fire. 95% of the work has been done toward containment.
RETENTION POND: This 1,125 acre (455 ha) fire. The location in Florida was not reported. 123 people are working on this fire. 80% of the work has been done toward containment.
CARLTON RESERVE: This 6,250 acre (2530 ha) fire. The location in Florida was not reported. 2 people are working on this fire. 50% of the work has been done toward containment.
MUSE AREA: This 600 acre (243 ha) fire. The location in Florida was not reported. 95% of the work has been done to contain the fire. 6 people are working on the fire.
MORRIS BRIDGE RD: This 600 acre (243 ha) fire. The location in Florida was not reported. 70% of the work has been done toward containment. 10 people are working on this fire.
DANVILLE: This is a 500 acre (202 ha) fire. The location in Florida was not reported. It is unknown what percent of the work has been done toward containment or how many people are working on the fire. Colorado BOBCAT: This 2,000 acre (809 ha) fire is burning on the Arapaho-Roosevelt National Forest, 12 miles (19 km) west of Loveland, Colorado. Evacuation of 150 to 200 homes is occurring. Five homes have been destroyed. 0% of the work has been completed for containment of this fire. 105 people are working on the fire.
HIGH MEADOW: This 1,800 acre (728 ha) fire is burning on Colorado State Forest Service protected lands 35 miles (56 km) southwest of Denver, near Bailey, Colorado. Three homes and two outbuildings have been destroyed and 100 more homes are threatened. Evacuations are underway. 0% of the work has been completed for containment of this fire. 97 people are working on the fire. Utah WING: This 700 acre (283 ha) human caused fire is burning on the Uinta National Forest near the city of Springville, Utah. 70% of the work has been completed to contain of this fire. 208 people are working on the fire.
The National Interagency Fire Center (NIFC) Wildland Fire Update (13 June 2000)
Two large fires in Colorado destroyed several homes and continue to threaten structures in nearby communities. The Bobcat fire is burning in grass, brush and timber 12 miles (19 km) west of Loveland, Colorado. The High Meadow fire has burned about 1,800 (728 ha) so far near Bailey, which is 35 miles southwest of Denver.
There are 18 large fires reported for Florida, but expected rain showers should bring some relief to firefighting efforts throughout the state during the next few days.
Rehabilitation efforts continue on the Cerro Grande fire area near Los Alamos, New Mexico, and is scheduled to be completed by July 1st. Visit the Burned Area Emergency Rehabilitation Team web site for more information about these efforts.
Almost 400 new fires were reported yesterday from nearly every region of the country. There are currently 26 large fires are burning in Arizona, California, Colorado, Florida, New Mexico and Utah for a total of 67,616 acres (27,363 ha).
Fig. 6. Large Wildland Fires in the United States, 13 June 2000.
(National Interagency Fire Center)
NIFC Incident Management Situation Report (12 June 2000) Current Situation:
New large fires were reported in the Rocky Mountain, Southwest and Southern California Areas. Two Type I Incident Management Teams were mobilized in the Rocky Mountain Area as warm and windy conditions contributed to large fire growth near urban interface areas. Initial attack activity was light to moderate throughout the country. Mobilization of resources through the National Interagency Coordination Center increased. Very high to extreme fire indices were reported in Colorado, New Mexico, Arizona, California, Utah, Nevada, Wyoming, Texas, Oklahoma, Kansas, Minnesota, Florida, Georgia, and Mississippi. Outlook:
A Fire Weather Watch is posted for northern New Mexicofor strong winds and low relative humidities.
A Red Flag warning is posted in the Sacramento Valley of Northern California for gusty winds, low relative humidities, and well above normal temperatures.
A Fire Weather Watch is posted for central California for moderate winds, hot temperatures and low relative humidities.
The Great Basin, the Southwest and Colorado will be cooler and drier as a cold front moves east through the Rocky Mountains. Colorado will have mixed light rain and showers. Eastern and southwest New Mexico will have a chance of thunderstorms. The rest of the area will be partly cloudy. Temperatures will range from the 70’s (21-26°C) in the mountains to near 105 (40 °C) in the deserts. Winds will be west to northwest at 15 to 25 mph. (24-40 km/h) Minimum relative humidities will be 5 to 15 percent in desert areas and 15 to 30 percent elsewhere.
Florida will have partly cloudy conditions with scattered showers and thunderstorms. High temperatures will be in the mid 80’s (29°C) to the lower 90’s (33°C). Winds will be south to southeast at 5 to 10 mph (8-16km/h). Minimum relative humidities will be 50 to 60 percent.
Southern California will be sunny and hot. High temperatures will be in the 70’s (21-26°C) and 80’s (27-31°C) along the coast, 90 (32°C) to 105 (40°C) inland and up to 115 (46°C) in the deserts. Winds will be variable at 5 to 15 mph. Minimum relative humidities will range from 40 to 50 percent on the coast to less than 10 percent in the deserts.
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 30 and 90-day forecast maps).
Tab.1. Five-Year Wildland Fire Comparison Statistics Year-to-Date for the United States (12 June 2000)
(Source: National Interagency Fire Center (NIFC)
As of 12 June 2000Number of Wildland FiresArea burntAcresHectars 2000 44,318 1,210,368 489,818 1999 43,583 854,206 345,684 1998 25,873 596,365 241,340 1997 29,772 475,258 192,330 1996 61,008 1,848,917 748,230
NIFC Wildland Fire Potential Assessment (8 June to 6 July 2000): ALASKA – Potential: normal. Temperatures have been below normal and precipitation has been above normal for the last six weeks. May was the second coolest in the past 35 years, and green-up was a week or more later than usual. Currently south-central Alaska has the greatest fire potential. Thunderstorm activity should increase later this month and cause a normal amount of fire activity in the interior. NORTHWEST – Potential: Below normal to normal. Temperatures and precipitation have been normal for the past month. Live fuel moistures are above average and have been measured at 121% in central Oregon to 131% in eastern Washington. 1000 hour dead fuel moistures have been above normal in most of the area and generally are being measured from 28% in the west to 17% in the eastern regions. Low potential for fire occurrence and severity is expected for most of the area. In the lower elevations of eastern Washington and Oregon, predicted warmer and drier than normal weather conditions will lead to a normal potential for fires. CALIFORNIA – Potential: Normal to above normal. Precipitation has been below normal and temperatures have been above normal in southern California. In the north both temperature and precipitation have been normal. Some moderate drought conditions still exist in southern California. 1000 hour fuel moistures are normal for this time of year throughout the area. Precipitation received in June will be critical to determining the rest of the season for northern California. The May pattern of less marine influence on southern California will likely continue through June, promoting the likeliness of above average temperatures and low humidities. NORTHERN ROCKIES – Potential: Normal. Precipitation has been below normal and temperatures have been above normal during the last month in most of the area except for northern Idaho, where both have been normal. Live fuel moisture is below normal east of the Continental Divide. 1000 hour dead fuel moisture is running 9 to 12 percent below normal and is measured at 13 to 21%. Eastern and central Montana are experiencing moderate to severe drought conditions, but wetting rains at the end of May have brought some relief. If normal June rains occur, fire occurrence will be average. GREAT BASIN – Potential: Normal to above normal. Temperatures have been above normal during the past month while precipitation has been normal to below normal through the area. Snowpack is 45 to 80 percent of normal in the higher elevations, and most areas are reporting that they are two to three weeks ahead of normal fire season, because of the mild winter. Frost-killed fuels are a concern in eastern Utah. Fine fuel carryover from the past several years is contributing to increased risk of fire activity in Nevada. 1000 hr fuel moistures were measured at 10 to 25% throughout the Great Basin and are 10% below normal in Nevada. Moderate to severe drought conditions are being reported in both southern Nevada and southern Utah. SOUTHWEST – Potential: Above normal. Precipitation has been below normal everywhere except in southeastern Arizona, where it has been normal. Temperatures have been above normal in all parts of the region, as much as 5 to 8 degrees Fahrenheit. Long range forecasts call for above normal temperatures to persist during this month. Long range outlook indicates above normal precipitation for Arizona and New Mexico. 1000 hour fuel moistures are below normal in the central and southern regions and normal in the north. Live fuel moisture is in the 50 to 90 percent range everywhere except the northern portions of both state where live fuel moistures are measured in the 70 to 110 percent ranges. PDI indicates that moderate to severe drought conditions continue throughout all of Arizona and all except the northeast part of New Mexico. ROCKY MOUNTAIN – Potential: Normal to above normal. Precipitation has been normal to below normal and temperatures have been normal to above normal in the past month. Live fuel moistures have been normal except in southern and western Colorado, where they have been up to 40 percent below normal. 1000 hour fuel moistures are below normal for this time of year at 7 to 12% in the west and 10 to 14% in the east. Fire activity is expected to be above normal in southwestern Colorado and in southwestern Wyoming. Due to the anticipated weather pattern where waves of moisture move through about once a week, fire events should be of high intensity but relatively short duration. EASTERN – Potential: Normal to above normal. Temperatures and precipitation have been normal in most of the Eastern Area, except in the Upper Great Lakes region, where precipitation has been below normal. 1000 hr fuels are being measured in the 19 to 25% ranges, approximately 3% below normal for this time of year. Moderate to severe drought conditions exist in the central Midwest and the upper Great Lakes region. Green-up and increased precipitation over the past two weeks have significantly reduced fire danger everywhere except in the Upper Great Lakes area. SOUTHERN -Potential: Normal to above normal. Temperatures have been above normal and precipitation has been normal to below normal through most of the area last month. Approximately one third of the area has a soil moisture deficit of six inches or more. Long-term precipitation anomalies are substantial over most of the region. Southern Louisiana, Georgia, western South Carolina, and central Florida all report extreme drought conditions. 1000 hour fuel moistures are being measured at 7% in parts of Florida and around 20% in the rest of the area.
Temperatures and Precipitation reflect conditions over the past four to six weeks. The long range forecast is for the next 30 days. Above and below normal is indicated above in the narrative, areas not mentioned fall in the climatology category which means there are equal chances of being below normal(33.3%), normal (33.3%) or above normal (33.3%).
Fig.8. Map describing the wildland fire potential (8 June – 6 July 2000) for areas throughout the country.
(Source: National Interagency Fire Center)
Remarks on Prescribed Burning
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.