One of the Predictive Services offices issued a Fuels and Fire Behavior Advisory for southern California. In this new one, most of Northern California has been temporarily removed due to the unseasonably cool and wet weather pattern. With the forecast for the weather pattern to make a dramatic change mid-week with strong high pressure developing over California for rapid drying/warming into the weekend, they anticipate Northern CA will once again warrant an advisory in the next 1-2 weeks.
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“Fuels and Fire Behavior Advisory
Southern California
June 25, 2013
Subject: Low live and dead fuel moistures, along with persistent drought have created the potential for active to extreme fire behavior in Southern California.
Discussion: All of California is experiencing drought conditions. Effects of lower than normal live and dead fuel moistures and observed fire behavior for 2013 are the focus of this advisory. Note that most of Northern CA was included in the previous advisory but has been temporarily removed due to forecasted widespread wetting rain. It is anticipated that area will warrant an advisory in the next couple weeks.
Difference From Normal Conditions: Drought conditions ranging from abnormally dry to severe exist and are expected to persist or intensify. The entire area is deficient in rainfall and snow pack, resulting in fuels that are 4-8 weeks ahead of normal drying/curing rates.
Concerns to Firefighters:
- Energy Release Component (ERC) values at numerous weather stations are well above normal and many are at record maximums. Expect increased fire intensity and spread rates in these areas. Early season extreme fire behavior has been observed especially in brush fuel types. Anticipate increased spread rates, spotting, and active night time burning.
- The combination of persistent drought and record-low rainfall and snowpack amounts has led to very low live and dead fuel moistures. Low 1000-hour fuel moistures have been evidenced by complete consumption of dead fuels on recent fires. Live fuel moistures for Chamise have already reached critical levels of 60% or less in many areas. Expect fires to ignite easier and spread faster. Anticipate higher resistance to control in all fuel types.
- Active fire behavior can extend well into the night and early morning hours even with moderate RH recovery. Already this year, Southern California has experienced large fire activity and multiple team deployments. It is important to be mindful of and manage fatigue for all resources. Everyone, every day, returns home safely.
Mitigation Measures:
- Local and inbound fire personnel need to be aware that fire behavior is exceeding normal expectations for this time of the year. Local briefings need to be thorough and highlight specific fire environment conditions. These include but are not limited to local weather forecasts, Pocket Cards, ERC’s, live and dead fuel moistures, and special fuel conditions such as mortality, Sudden Oak Death and frost killed brush, etc.
- Suppression actions need to be based on good anchor points, escape routes, and safety zones. Remember LCES. Experienced lookouts are essential under these conditions.
- Base all actions on current and expected behavior of the fire. Augment initial attack resources as incident activity dictates.
- Review the most current Southern California 7-day Significant Fire Potential along with Daily, Monthly and Seasonal Outlooks at: http://www.predictiveservices.nifc.gov/outlooks/outlooks.htm
Area of Concern: The area of concern is the Southern California geographic area with the exception of 4 PSA’s: Central Valley, Central Mojave, Eastern Desert, and Lower Deserts. A map showing the areas of concern described in this advisory can be found at: National Fuel Advisories
Issued: June 25, 2013 (Note this advisory will be in effect for 14 days and will be reviewed/updated at that time.)”
