Fire Weather

John Horel

NOAA Cooperative Institute for Regional Prediction

Department of Meteorology

University of Utah

Fire Weather Internet Resources

National Fire plan: www.fireplan.gov

National Interagency Fire Center (NIFC): www.nifc.gov

GACCs: www.nifc.gov/fireinfo/geomap.html

Fire Danger PocketCards: famweb.nwcg.gov/pocketcards

GeoMAC: geomac.usgs.gov

DRI: www.wrcc.dri.edu/fire/FW2.html

Wildland Fire Assessment System: www.fs.fed.us/land/wfas/

Fire terminology

Crown fire - a severe fire where flames travel from tree to tree at the level of the tree’s crowns or tops.

Fire line - a zone along a fire’s edge where there is little or no fuel available to the fire

Backfire - a fire started to stop an advancing fire by creating a burned area in its path

Firebrand - flaming or glowing fuel particles that can be carried naturally by wind, convection currents or gravity into unburned fuels

Spotting - outbreak of secondary fires as firebrands or other burning materials are carried ahead of the main fire by winds

wildfire - an unwanted fire that requires measures of control.

firing pattern - the specific pattern and timing of ignition of a prescribed fire to affect the direction or rate of fire spread and fire intensity.

Red Butte. Salt Lake City

Springville. June 30, 2002

Spruce & subalpine fir crowning

Spot fire 0.8 km from main fire (crowning)

http://lwf.ncdc.noaa.gov/oa/reports/billionz.html#LIST

Trend in # Fires and Total Yearly Acreage

Top Ten Fire Years: 1960-2002

Selected Major Historical Fires

Peshtigo, Wisconsin Fire

Oct. 8–14 1871

over 1,500 lives lost and 3.8 million acres burned in nation's worst forest fire

Weather: prolonged and widespread drought and high temperatures, capped off by a cyclonic storm in early October

Started same day as Chicago fire (cow/lantern)

http://www.peshtigofire.info/

Fires: 1981-2000
http://www.fs.fed.us/r4/rsgis_fire/

Fire Triangle

Topography

The most constant in time of the three factors, but may vary over space.

Elevation, aspect, slope steepness, landform characteristics.

Linked to spatial variations in climate (determines fuel type and loading) and temporal and spatial variations in weather.

Fire shape & intensity pattern depend on slope angle, orientation, wind direction and speed

The fire environment

fuels

weather

topography

Fuels, continued

The amount of wildland fuel available for burning depends on fuel moisture, which depends directly on past and present atmospheric humidity and precipitation.

Different fuels respond to changes in humidity and precipitation at different rates.

Fuel moisture content

The most important variable in determining fire ignition, rate of combustion, and energy output from fire.

fmc = 100 * (field weight-oven dry weight)/ODW

dead fuels, 1.5-30% moisture content

live fuels, 35-200% moisture content

Live FMC varies seasonally with phenology.

Dead FMC varies daily with moisture.

Fire Danger Rating uses Dead FMC as a key component.

Dead fuels

Four size classes with characteristic reaction times (time lags) to changes in atmospheric moisture

1-h 0 to 0.25" (0-6mm)

10-h 0.25 to 1.0" (6 to 25mm)

100-h 1.0 to 3.0" (25 to 76mm)

1000-h 3.0 to 8.0" (76 to 203mm)

Time lag concept, 10-hr fuels

Diurnal changes in relative humidity

Weather

Is the most variable over time and is the most difficult for the resource manager to predict.

Directly affects fire behaviour and significantly affects smoke production and dispersion.

Lightning, strong winds, precipitation and humidity

Automatic fire weather stations

In-the-field weather support

Indicators of stable air

Indicators of unstable air

Summit fire (OR), plume-dominated. Lightning and downbursts developed in convective column

Beneficial fires - to meet resource management objectives:

to reduce the danger of large catastrophic fires

to prepare land for planting

to control spread of disease or insect infestations

to benefit plant species that are dependent on fire

to influence plant succession

to alter soil nutrients

Prescribed fire

Firing patterns

Backfiring in light grass at Kingman, AZ, June 1994

Prescribed burning, AZ, Nov 1995. Was burned also in 1989 and 1992. Quantity and duration of smoke was greatly reduced on 2nd and 3rd burns.

Backfiring in heavy fuels near McCall, Idaho, Aug 1994

Prescribed fires in western OR

Smoke management

Plumes from E Oregon and central Idaho fires, 29 July 1989

Satellite photo of smoke transport

Smoke creates hazardous flying conditions near fire camp

Summary

Drought in the West

Fuel/Vegetation

Evolution of Greenness: 2002

Slide 45

Slide 46

Hayman Fire

Slide 48

Slide 49

Aftermath

Slide 51

Rodeo-Chediski

Slide 53

"QLCA3"

QLCA3

Slide 55

Biscuit Fire

Slide 57

Aug. 16: http://www.fs.fed.us/eng/rsac/fire_maps.html

Weather

Seattle Times Thursday, December 12, 2002

Sweeping shift in forest policy: Bush plan would skip environmental reviews

WASHINGTON — In a sweeping forest-policy revision, the Bush administration announced plans yesterday to fundamentally alter how it manages federal lands by skipping extensive environmental reviews in the name of wildfire prevention.

The proposal is part of a strategy to streamline environmental laws and help the land-management bureaucracy tick along more smoothly. It would allow the administration, in many cases, to skip traditional environmental analysis for projects that reduce wildfire risks or rehabilitate forests after wildfires occur.

But environmentalists saw the changes as an attempt to remove the public's voice from decision-making while the administration tries to boost logging on federal lands. And some in Congress viewed the proposals as an attempt to sidestep lawmakers.

The debate heated up last fall, after more than 7 million acres burned nationwide and President Bush announced his "Healthy Forests Initiative." The plan called for a range of changes, from limiting bureaucratic processes and appeals to expediting work that reduces wildfire dangers.

Drought and Fire Outlook

Summer ’03?


	John Horel
	NOAA Cooperative Institute for Regional Prediction
	Department of Meteorology
	University of Utah


	National Fire plan: www.fireplan.gov
	National Interagency Fire Center (NIFC): www.nifc.gov
	GACCs: www.nifc.gov/fireinfo/geomap.html
	Fire Danger PocketCards: famweb.nwcg.gov/pocketcards
	GeoMAC: geomac.usgs.gov
	DRI: www.wrcc.dri.edu/fire/FW2.html
	Wildland Fire Assessment System: www.fs.fed.us/land/wfas/


	Crown fire - a severe fire where flames travel from tree to tree at the level of the tree’s crowns or tops.

	Fire line - a zone along a fire’s edge where there is little or no fuel available to the fire

	Backfire - a fire started to stop an advancing fire by creating a burned area in its path

	Firebrand - flaming or glowing fuel particles that can be carried naturally by wind, convection currents or gravity into unburned fuels

	Spotting - outbreak of secondary fires as firebrands or other burning materials are carried ahead of the main fire by winds

	wildfire - an unwanted fire that requires measures of control.

	firing pattern - the specific pattern and timing of ignition of a prescribed fire to affect the direction or rate of fire spread and fire intensity.


		Oct. 8–14 1871
				over 1,500 lives lost and 3.8 million acres burned in nation's worst forest fire
				Weather: prolonged and widespread drought and high temperatures, capped off by a cyclonic storm in early October
				Started same day as Chicago fire (cow/lantern)
				http://www.peshtigofire.info/


	The most constant in time of the three factors, but may vary over space.

	Elevation, aspect, slope steepness, landform characteristics.

	Linked to spatial variations in climate (determines fuel type and loading) and temporal and spatial variations in weather.


	The amount of wildland fuel available for burning depends on fuel moisture, which depends directly on past and present atmospheric humidity and precipitation.

	Different fuels respond to changes in humidity and precipitation at different rates.


	The most important variable in determining fire ignition, rate of combustion, and energy output from fire.
	fmc = 100 * (field weight-oven dry weight)/ODW
	dead fuels, 1.5-30% moisture content
	live fuels, 35-200% moisture content
	Live FMC varies seasonally with phenology.
	Dead FMC varies daily with moisture.
	Fire Danger Rating uses Dead FMC as a key component.


	Four size classes with characteristic reaction times (time lags) to changes in atmospheric moisture

	1-h 0 to 0.25" (0-6mm)
	10-h 0.25 to 1.0" (6 to 25mm)
	100-h 1.0 to 3.0" (25 to 76mm)
	1000-h 3.0 to 8.0" (76 to 203mm)


	Is the most variable over time and is the most difficult for the resource manager to predict.

	Directly affects fire behaviour and significantly affects smoke production and dispersion.

	Lightning, strong winds, precipitation and humidity


	to reduce the danger of large catastrophic fires

	to prepare land for planting

	to control spread of disease or insect infestations

	to benefit plant species that are dependent on fire

	to influence plant succession

	to alter soil nutrients


	Sweeping shift in forest policy: Bush plan would skip environmental reviews
	WASHINGTON — In a sweeping forest-policy revision, the Bush administration announced plans yesterday to fundamentally alter how it manages federal lands by skipping extensive environmental reviews in the name of wildfire prevention.
	The proposal is part of a strategy to streamline environmental laws and help the land-management bureaucracy tick along more smoothly. It would allow the administration, in many cases, to skip traditional environmental analysis for projects that reduce wildfire risks or rehabilitate forests after wildfires occur.
	But environmentalists saw the changes as an attempt to remove the public's voice from decision-making while the administration tries to boost logging on federal lands. And some in Congress viewed the proposals as an attempt to sidestep lawmakers.
	The debate heated up last fall, after more than 7 million acres burned nationwide and President Bush announced his "Healthy Forests Initiative." The plan called for a range of changes, from limiting bureaucratic processes and appeals to expediting work that reduces wildfire dangers.