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Extreme Fire Behavior – II

 

Fire managers make decisions throughout the day on how to suppress fires and best use resources while protecting life and property. This Standard Firefighting Order depicts a firefighter observing increased fire behavior during a time of day when temperatures are high and relative humidity is low.

3. Base all actions on current and expected behavior of the fire. A firefighter looks at his watch, which reads 2 PM, while a fire actively grows in steep terrain and heavy timber.

3. Base all actions on current and expected behavior of the fire.

Read about all 10 Standard Firefighting Orders.

Changes in fire behavior are always present in incidences of shelter deployment. Firefighters need to maintain situation awareness of live and dead fuel moisture conditions, as well as predicted and current weather conditions. As fire behavior moves from mild to moderate to extreme, it is critical to respond correctly to the changing situation.

Discuss how the following factors can contribute or lead to extreme fire behavior:

  • Frost kill: late or unusually extensive freezes, high loading of frost-killed fuels.
  • Drought Conditions: Live Fuel Moistures Index, Keetch-Byram Drought Index (KBDI), Soil Moisture Index, low humidity, high temperatures.
  • Slope: increases fire spread uphill, preheats fuels by convection; may channel winds.
  • Sea Breeze/Foehn: wind direction may vary throughout the day; humidity changes may occur; strong wind velocities may drive fire behavior.

To aid situation awareness:

  • Track National Fire Danger Rating System (NFDRS) live and dead fuel moisture outputs.
  • Take hourly weather observations and track the hourly changes. By tracking fuel moisture and weather observations and using the Fire Severity Related to Fuel Moisture Chart, firefighters can be alerted to conditions leading to situations where there is a high potential for extreme fire behavior.

 

Category
Weather Fire Behavior
References
National Fire Danger Rating System Information
10 Standard Firefighting Orders, PMS 110
10 and 18 Poster, PMS 110-18
18 Watch Out Situations, PMS 118
Extreme Fire Behavior 1 6MFS Topic

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NWCG Latest Announcements

NEW! Air Operations Summary (ICS 220 WF) Now Available

Date: May 2, 2025
Questions?  Please contact:
National Interagency Aviation Committee

The Air Operations Summary (ICS 220 WF) provides the Air Operations Branch with the number, type, location, and specific assignments of helicopters and air resources. The new ICS 220 WF also includes medical extraction capabilities and air resources tracking.

Understanding the capabilities of aviation assets is critical for effective medical and extraction responses. Coordination with the Medical Unit Leader is essential to ensure alignment and consistency between the ICS 220 WF and the Medical Plan (ICS 206 WF). 

References:

Air Operations Summary (ICS 220 WF)

National Interagency Aviation Committee

Incident Command System (ICS) Forms

Incident Position Standards and Next Generation Position Task Book Available for Firing Boss, Single Resource

Date: April 30, 2025
Questions?  Please contact:
Fuels Management Committee

NWCG is excited to announce that the NWCG Incident Position Standards for Firing Boss, Single Resource, PMS 350-105, and the NWCG Position Task Book for Firing Boss, Single Resource (FIRB), PMS 311-105, are now available. 

These resources, part of the Performance Support Package developed through the Incident Performance and Training Modernization (IPTM) effort, support trainees, qualified personnel, and evaluators. 

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.

 

References:

NWCG Firing Boss, Single Resource Position Page

NWCG Incident Position Standards for Firing Boss, Single Resource, PMS 350-105

NWCG Position Task Book for Firing Boss, Single Resource (FIRB), PMS 311-105

Incident Position Standards and Next Generation Position Task Book Available for Helicopter Crewmember

Date: April 28, 2025
Questions?  Please contact:
Interagency Helicopter Operations Subcommittee

NWCG is excited to announce that the NWCG Incident Position Standards for Helicopter Crewmember, PMS 350-22, and the NWCG Position Task Book for Helicopter Crewmember (HECM), PMS 311-22, are now available.

These resources, part of the Performance Support Package developed through the Incident Performance and Training Modernization (IPTM) effort, support trainees, qualified personnel, and evaluators.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.

References:

NWCG Incident Position Standards for Helicopter Crewmember, PMS 350-22

NWCG Incident Position Standards for Helicopter Crewmember, PMS 350-22

NWCG Position Task Book for Helicopter Crewmember (HECM), PMS 311-22

Updated NWCG Standards for Fire Unmanned Aircraft Systems Operations, PMS 515

Date: April 23, 2025
Questions?  Please contact:
Interagency Fire Unmanned Aircraft Systems Subcommittee

The NWCG Standards for Fire Unmanned Aircraft Systems Operations, PMS 515 standardizes processes and procedures for the interagency use of Unmanned Aircraft Systems (UAS), including pilot inspections and approvals. This updated publication provides the aviation community with standards to ensure UAS are used safely, effectively, and efficiently in support of fire management goals and objectives.

References:

NWCG Standards for Fire Unmanned Aircraft Systems Operations, PMS 515

NWCG National Interagency Aviation Committee