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Extreme Fire Behavior – I

 

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 have always been present in cases of shelter deployment. It is critical for firefighters 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 act decisively regarding the changing situation.

Discuss the following indicators of extreme fire behavior:

  • Relative humidity less than 15%.
  • 1-hour fuel moisture less than 5%.
  • Transition from surface to crown fire.
  • Smoldering fires that exist in the early part of the day are beginning to burn very actively as the day progresses.
  • Approaching thunderheads with dark clouds beneath.
  • Presence of dust devils indicating atmospheric instability.
  • Increased spotting.
  • Sudden calm.
  • High clouds moving fast in a direction that is different from surface wind.
  • Predicted Haines Index of 5 and 6 in those areas where this level is a good indicator of atmospheric instability.
  • Fire whirls.

Image of a fire whirl twisting up from a forest fire.

 

Category
Weather - Fire Behavior

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Quarter Three Materials for the 2025-2026 Wildland Fire Leadership Campaign Now Available

Date:  April 1, 2026
Questions? 
Please contact: Leadership Committee

NWCG is excited to announce that Quarter Three materials for the 2025/2026 Wildland Fire Leadership Campaign are now available. This annual initiative offers all students of leadership and wildland fire management an opportunity to engage with essential leadership skills and knowledge needed to lead effectively in dynamic environments.

Quarter Three materials focus on Leadership Level 3: Leader of People (Develop Intent). Leadership Level 3 is where your values, your team, and your influence come together. Leaders of People put their teams first, build trust, and lead with authenticity. They mentor future leaders and shape decisions up and down the chain.

References:

2025/2026 NWCG Leadership Campaign - Leadership Levels

Wildland Fire Leadership Development Program

Leadership Committee

WFSTAR 2026 Core Components Module Package and 2025 Fire Year in Review Now Available

Date:  March 23, 2026
Questions? 
Please contact: Joe Schindel

The 2026 Core Components Module Package for RT-130, Wildland Fire Safety Training Annual Refresher (WFSTAR) and the 2025 Fire Year in Review are now available on the NWCG website. The 2026 Core Components Module Package provides all content needed to deliver RT-130.

References:

2026 Core Components Module Package

2025 Fire Year in Review Module

NEW! S-490, Advanced Fire Behavior Calculations (Blended) Available Now

Date:  March 17, 2026
Questions? 
Please contact: Fire Behavior Subcommittee

NWCG is pleased to announce that the new S-490, Advanced Fire Behavior Calculations (Blended), 2026 course is now available.

This training includes performance-based activities that allow students to apply the knowledge and concepts required for the Fire Behavior Analyst (FBAN), Long Term Fire Analyst (LTAN), and Prescribed Fire Burn Boss Type 1 (RXB1) positions. It supports individuals working towards these incident qualifications.

This blended course begins with a self-paced online training (OLT) in the Wildland Fire Learning Portal (WFLP), followed by an in-person instructor-led training (ILT).

References:

S-490, Advanced Fire Calculations (Blended)

NWCG Fire Behavior Analyst (FBAN) Position Page

NWCG Long Term Fire Analyst (LTAN) Position Page

NWCG Prescribed Fire Burn Boss Type 1 (RXB1) Position Page

2024 Paul Gleason Award Winners Announced

Date:  March 13, 2026
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Please contact: Leadership Committee

The NWCG Leadership Committee is proud to announce the recipients of the 2024 Paul Gleason "Lead By Example" awards. Award categories include Initiative and Innovation, Mentoring and Teamwork, Motivation and Vision, as well as a Lifetime Achievement Award.

Congratulations to the awardees:

  • Justin Baxter, National Unmanned Aerial System (UAS) Operations Specialist, with the U.S. Forest Service — Initiative and Innovation
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References:

Paul Gleason Lead By Example Award

Wildland Fire Leadership Development Program (WFLDP)

Leadership Committee