Space WX Alerts: EXTENDED WARNING:  Geomagnetic K-index of 4 expected ( Latest Alert ) - Issue Time: 2020 Sep 28 2354 UTC
Radar Local Radar
Click Map To Animate Lightning 89.1°F  16% CBI: 122 Chandler Burning Index Description Fire Weather Index icons
Live FWI: 21
Fire Weather Index icons
Live FWI10: 31.9
Current Conditions for Foresthill, CA.
Updated9/28/20  5:39pm
Current Fire Danger
icon  Red Flag Warning  -  Redding, CA  -  Mendocino Coast  -  Foresthill, CA  -  Modesto, CA  -  Sacramento, CA  -  Donner Summit  -  Blue Canyon
icon  Heat Advisory  -  San Francisco, CA
icon  Air Quality Alert  -  Yosemite Area

Fire locations are based on data provided by the National Interagency Coordination Center and are subject to change.

Move your mouse over the fire indicators to see additional information.

Printable Map
View High
Resolution Map
Definition of
Map Terms
KMZ File
'RED SALMON COMPLEX' - 110112.0 acres 'SLATER' - 154102.0 acres 'AUGUST COMPLEX WEST ZONE' - 104877.0 acres 'DEVIL' - 8410.0 acres 'FOX' - 2188.0 acres 'WOODWARD' - 4929.0 acres 'AUGUST COMPLEX' - 768243.0 acres 'ARCHIE CREEK' - 131542.0 acres 'S. OBENCHAIN' - 32671.0 acres 'ZOGG' - 7000.0 acres 'GLASS' - 11000.0 acres 'OR-WIF-200430' - 173094.0 acres 'BEACHIE CREEK' - 192838.0 acres 'THIELSEN' - 9971.0 acres 'RIVERSIDE' - 138029.0 acres 'BIG HOLLOW' - 24995.0 acres 'TWO FOUR TWO' - 14473.0 acres 'LIONSHEAD' - 204340.0 acres 'DOLAN' - 128417.0 acres 'WHITE RIVER' - 17383.0 acres 'DOWNEY CREEK' - 3166.0 acres 'NORTH COMPLEX' - 305188.0 acres 'POWER LINE' - 175.0 acres 'BRATTAIN' - 50951.0 acres 'FORK' - 1667.0 acres 'BLUEJAY' - 4488.0 acres 'WOLF' - 1087.0 acres 'SLINK' - 26759.0 acres 'CREEK' - 302870.0 acres 'BULLFROG' - 1185.0 acres 'MORAINE' - 668.0 acres 'SQF COMPLEX' - 150266.0 acres 'RATTLESNAKE' - 4070.0 acres 'BOBCAT' - 114103.0 acres 'WEST BRANCH' - 113.0 acres 'EL DORADO' - 22680.0 acres 'WOODHEAD' - 95985.0 acres 'SNOW' - 6254.0 acres 'BERNARD' - 1375.0 acres 'NORTH CASCADE COMPLEX' - 2584.0 acres 'CALLAHAN' - 1276.0 acres 'BUCK' - 19474.0 acres 'PORPHYRY' - 14486.0 acres 'SHISSLER' - 10680.0 acres 'GROUSE' - 3980.0 acres 'SPONGE' - 610.0 acres 'LEGGIT' - 820.0 acres 'WARM SPRINGS' - 119.0 acres 'DOUBLE' - 1143.0 acres 'MARION' - 1520.0 acres 'BEAVER' - 2992.0 acres 'BADGER' - 89847.0 acres 'VIRGIN MOUNTAIN' - 1624.0 acres 'CINNABAR' - 2948.0 acres 'LION CREEK' - 195.0 acres 'GARNET' - 866.0 acres 'BEAR CREEK' - 12150.0 acres 'DRUMMING' - 4351.0 acres 'STATE CREEK' - 4400.0 acres 'SEARS' - 9200.0 acres 'LOBO MESA' - 330.0 acres 'WILLIAM' - 5832.0 acres 'BRIDGER FOOTHILLS' - 8224.0 acres 'LONE STAR' - 4123.0 acres 'EAST FORK' - 69244.0 acres 'CENTER CREEK TRAIL' - 1225.0 acres 'GASS FLATS' - 10744.0 acres 'MIDDLE FORK' - 7897.0 acres 'MULLEN' - 77950.0 acres 'WILLIAMS FORK' - 12898.0 acres 'CAMERON PEAK' - 124026.0 acres
Today's Outlook
Day 1 Fire Weather outlook
Tomorrow's Outlook
Day 2 Fire Weather outlook
Day 3-8 Outlook
Day 3 through Day 8 Fire Weather outlook
Month 1 Outlook
Month 2 Outlook
Month 3 Outlook

Fire Weather Warnings, and Watches

Temperature, Humidity and Wind

Temperature Maps
Temperature Maps
Humidity Maps
Humidity Maps
Wind Maps
Wind Maps
Fire Information - National Fire News

Northern California Preparedness Level 5  

National Preparedness Level 5  

National Preparedness Level Updated August 18 at 8 p.m. MDT (on a scale from 1 to 5)

September 28, 2020

Light wildland fire activity was reported yesterday. Two new large fires were reported in California. No large fires were contained although firefighters continue to achieve their suppression goals as we near the end of September.

NIMO (Houseman) has been assigned to COVID-19 support at Forest Service headquarters in Washington, D.C. NIMO (Reinarz) has been assigned to provide wildland fire support to California. NIMO (Day) has been assigned to provide wildland fire support to federal land management agencies in Oregon and Washington.  

Two hundred thirty-three soldiers from the 14th Brigade Engineer Battalion based out of Joint Base Lewis-McChord, Washington are deployed in support of the August Complex.

Two hundred thirty-four Marines from the 7th Engineer Support Battalion, 1st Marine Logistics Group, 1 Marine Expeditionary Force based out of Camp Pendleton, California are deployed in support of the Creek fire.

One RC-26 aircraft with Distributed Real-Time Infrared (DRTI) capability and support personnel from the 141st Air Refueling Wing (Washington Air National Guard) has been deployed to Fairchild AFB (Spokane, WA), in support of wildland fire operations.

Two MAFFS C-130 airtankers and support personnel from the 146th Airlift Wing (California Air National Guard) and one MAFFS C-130 airtanker and support personnel from each the 153rd Airlift Wing (Wyoming Air National Guard) and the 152nd Airlift Wing (Nevada Air National Guard) have been deployed to support wildland fire operations in California.

One fire suppression crew and one overhead personnel from Canada are supporting fire suppression efforts in northern California. Seven fire suppression crews, 18 fire engines and 54 overhead personnel from Canada are supporting fire suppression efforts in Oregon.

Five fire suppression crews and four overhead personnel from Mexico are supporting fire suppression efforts in southern California.

During this unprecedented time, the safety of the public and all wildland fire responders is always the number one priority for all wildland fire agencies. For more information and links to the Geographic Area Plans, visit the NIFC COVID-19 page.


Critical fire weather will continue for Northern California and portions of Southern California due to breezy offshore winds and very hot/dry conditions. Offshore winds are likely west of the Cascade Crest in Oregon as well, although humidities generally stay above critical values. Gusty winds are expected for much of the Great Plains and low humidities will result in elevated fire weather concerns for eastern Wyoming and Colorado as well as the Texas and Oklahoma Panhandles. Very dry conditions continue for the Southwest and Great Basin. Little to no measurable precipitation is expected across the West.

Local Weather: Monday, Sepember 28, 2020 - 2:42pm PDT
Red Flag Warning Continues Through 9 PM PDT Tonight
 InciWeb California Incidents  InciWeb National Incidents

Experimental Hourly Fire Danger

Entire California  | Northern California  | Central California  | Southern California

Lightning Ignited Fires

National Interagency Fire Center statistics show that in 2002-2006, an average of 12,000 (16%) of the wildland fires were started by lightning per year. These fires burned an average of 5.2 million acres per year.

   Two-thirds of lightning fires occur June-August. lightning fires peak in the late afternoon and early evening. Three-fifths (61%) of all fires started by lightning occurred between 2:00 and 10:00 p.m.

   55% of lightning fires occur outdoors, and 41% occur in structures. Deaths and injuries occur mostly in structures (89% and 86%, respectively).

   Because most lightning fires occur outdoors, the most prominent form of material ignited is "growing living form," which includes trees, brush, and grass. Materials found on residential structures that are commonly ignited include roofs, sidewalls, and framing. Electrical wiring is another material often ignited, as the electrical current in lightning is drawn to electrical wires.

   Civilians suffer more injuries than fatalities in lightning fires each year. Most casualties result from lightning structure fires rather than outside or other types of lightning fires. 89% of lightning fire civilian fatalities and 86% of injuries occur in structure fires.

Potential Outlook Maps

Fire Potential Outlook

Significant Fire Potential Outlooks
(click for more info)
Lightning Probability Forecast Map
Thunderstorm Probability
Current Lightning Efficiency Map
(click to enlarge)

Lightning Ignition Efficiency

Lightning fires are started by strikes to ground that have a component called a continuing current. All positive discharges have a continuing current, and about 20% of negative discharges have one. Ignition depends on the duration of the current and the kind of fuel the lightning hits. Ignition in fuels with long and medium length needle cast, such as Ponderosa pine and Lodgepole pine, depend on the fuel moisture. Ignitions in short- needled species, such as Douglas fir depend far more on the depth of the duff layer than on the moisture. Spread of the fire after ignition usually depends on fuel moisture in all cases.

The ignition efficiency on a 1 km pixel is given on a per discharge basis. That is, if the efficiency is high, then about 9 discharges will result in one ignition; if the efficiency is extreme, about 5 or fewer discharges will result in an ignition. The ratio of positive and negative discharges is built into the calculation. (Latham and Schlieter 1989) document the algorithm.

The fuel type and depth are conversions of the 1 km resolution current cover type (Hardy and others 1999) for this specific calculation. The moisture input is the 100-hr dead fuel moisture.

August 2002 - The lightning ignition efficiency algorithm has been corrected due to discovery of an error. The resulting maps reflect higher lightning efficiency than previously.

Current Lightning Efficiency Map
Current Lightning Efficiency Map

Haines Index (Wildfire Potential)

Haines (1988) developed the Lower Atmosphere Stability Index, or Haines Index, for fire weather use. It is used to indicate the potential for wildfire growth by measuring the stability and dryness of the air over a fire. It is calculated by combining the stability and moisture content of the lower atmosphere into a number that correlates well with large fire growth. The stability term is determined by the temperature difference between two atmospheric layers; the moisture term is determined by the temperature and dew point difference. This index has been shown to be correlated with large fire growth on initiating and existing fires where surface winds do not dominate fire behavior.

Haines Index is computed from the morning (12Z) soundings from RAOB stations across North America.

The Haines Index can range between 2 and 6. The drier and more unstable the lower atmosphere is, the higher the index.

  • 2 : Very Low Potential -- (Moist Stable Lower Atmosphere)
  • 3 : Very Low Potential
  • 4 : Low Potential
  • 5 : Moderate Potential
  • 6 : High Potential ------ (Dry Unstable Lower Atmosphere)
Current Haines Index Map
Haines Index Map

Fire Danger Maps

Each day during the fire season, national maps of selected fire weather and fire danger components of the National Fire Danger Rating System are produced by the Wildland Fire Assessment System (WFAS-MAPS), located at the USDA Forest Service Rocky Mountain Research Station in Missoula, Montana.

Current Observed Fire Danger Map
Observed Fire Danger Map
Current Forecast Fire Danger Map
Forecast Fire Danger Map
Current Observed Relative Humidity
Observed Relative Humidity
Current Observed Dew Point Levels
Observed Dew Point Levels
Current Observed Temperature
Observed Temperature
Forcast Wind Speed
Forcast Wind Speed

Keetch-Byram Drought Index

  Keetch and Byram (1968) designed a drought index specifically for fire potential assessment. It is a number representing the net effect of evapotranspiration and precipitation in producing cumulative moisture deficiency in deep duff and upper soil layers. It is a continuous index, relating to the flammability of organic material in the ground.

  The KBDI attempts to measure the amount of precipitation necessary to return the soil to full field capacity.

It is a closed system ranging from 0 to 800 units and represents a moisture regime from 0 to 8 inches of water through the soil layer. At 8 inches of water, the KBDI assumes saturation. Zero is the point of no moisture deficiency and 800 is the maximum drought that is possible. At any point along the scale, the index number indicates the amount of net rainfall that is required to reduce the index to zero, or saturation.

  The inputs for KBDI are weather station latitude, mean annual precipitation, maximum dry bulb temperature, and the last 24 hours of rainfall. Reduction in drought occurs only when rainfall exceeds 0.20 inch (called net rainfall). The computational steps involve reducing the drought index by the net rain amount and increasing the drought index by a drought factor.

Current - Keetch-Byram Drought Index
Keetch-Byram Drought Index


  • 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.

Chandler Burning Index Calculation
(0 - 120°F)
Relative Humidity
(0 - 100%)

Chandler Burning Index Fire Danger
powered by Cumulus v1.9.3 (1059)
Ambient Weather VWS v14.00
Top Website Map Copyright © 2007 - 2020 Never base important decisions on this or any weather information obtained from the Internet