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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 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

6MFS Suggestion Form


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NWCG Latest Announcements

NEW! S-219, Firing Operations (Blended) Now Available

Date: Sept 11, 2025
Questions? Please contact:
Fuels Management Committee 

The S-219, Firing Operations (Blended) course is now available on the Wildland Fire Learning Portal. Developed through the Incident Performance and Training Modernization (IPTM) effort, this training supports individuals working towards Firing Boss, Single Resource (FIRB) incident qualifications.

This blended course combines online and instructor-led training to provide students with the knowledge and skills required to perform the duties of the FIRB, as described in the NWCG Incident Position Standards for Firing Boss, Single Resource, PMS 350-105.

Any changes to qualification pathways will take effect with the next update of the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1, scheduled for January 2026.

References:

S-219, Firing Operations (Blended)

NWCG Firing Boss, Single Resource Position Page

Wildland Fire Learning Portal

NWCG Committees Observe Suicide Prevention Awareness Week: September 7-13, 2025

Date: Sep 5, 2025
Questions? Please contact:
Mental Health Subcommittee

The NWCG Mental Health Subcommittee (MHSC) and Risk Management Committee (RMC) recognize the unique challenges and demands faced by the wildland fire community. The MHSC and RMC know that we are all stronger together and believe in fostering a culture of support, understanding, and resilience.

Suicide Prevention Awareness encourages us to actively connect with and support each other. For more information that could make a difference for yourself or someone else please review the materials and resources provided for the 2025 Suicide Prevention Awareness Week.

References:

2025 Suicide Prevention Awareness Week Materials and Resources

NEW! Incident Performance and Training Modernization Story Map Now Available

Date: Aug 26, 2025
Questions? Please contact:
National Wildfire Coordinating Group

NWCG is excited to announce the launch of the Incident Performance and Training Modernization (IPTM) Story Map, a new interactive resource that showcases how NWCG is transforming wildland fire training and qualifications through a performance-based system.

Since its launch in 2023, IPTM has made major strides in updating how we manage incident positions:

  • 36 incident positions now have new Incident Position Standards and Next Generation Position Task Books available for field use
  • 6 more incident positions are nearing completion
  • 111 total incident positions are being analyzed through the IPTM initiative

The Story Map guides you through the IPTM process, highlights key accomplishments, and outlines what’s ahead. Whether you are a trainer or a trainee, this tool offers valuable insight into the modernization effort shaping the future of wildland fire training and qualifications.

This effort would not be possible without the contributions of NWCG staff, NWCG committees, and hundreds of subject matter experts across the wildland fire community.

References:

IPTM Story Map

Incident Performance and Training Modernization Webpage

NEW! S-290, Intermediate Wildland Fire Behavior (Blended) Available Now

Date: Aug 15, 2025
Questions? Please contact:
Fire Behavior Subcommittee

NWCG is excited to announce that the S-290, Intermediate Wildland Fire Behavior (Blended) training is now available on the Wildland Fire Learning Portal. S-290 (Blended) training combines online training and instructor-led training components that support individuals working towards any Single Resource Boss or Fire Effects Monitor incident qualifications.

This second course in the series collectively serves to develop fire behavior prediction knowledge and skills, and provides more detailed information on fuels, weather, and topography that affect wildland fire behavior for safety purposes.

Students are required to finish the prerequisite S-190, Introduction to Wildland Fire Behavior, before enrolling in S-290, Intermediate Wildland Fire Behavior (Blended).

References:

S-290, Intermediate Wildland Fire Behavior (Blended)

S-190, Introduction to Wildland Fire Behavior

Wildland Fire Learning Portal