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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.

References:

Category
Weather - Fire Behavior

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NWCG Latest Announcements

2026 Updates to the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1

Date: January 23, 2026
Questions? 
Please contact: Incident and Position Standards Committee

The Incident and Position Standards Committee has updated the NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1.

These updates address changes to incident position names and requirements for qualification, training, and experience. Updates related to the implementation of Complex Incident Management (CIM) and Incident Performance Training Modernization (IPTM) are also included.

The NWCG Wildland Fire Position Qualification Flowchart, PMS 308 has also been updated to reflect the recent changes.

References:

NWCG Standards for Wildland Fire Position Qualifications, PMS 310-1

NWCG Wildland Fire Position Qualification Flowchart, PMS 308

IPSC Memo 26-01: January 2026 Updates to the NWCG Standards for Wildland Fire Positions Qualifications, PMS 310-1

Incident Business Committee Memo 26-01: Updated Emergency Equipment Shift Ticket, OF 297

Date: January 22, 2026
Questions? 
Please contact: Incident Business Committee

The Incident Business Committee (IBC) has released Memorandum 26-01: OF 297 and 2026 Fire Use. This memo informs the wildland fire community that the updated Emergency Equipment Shift Ticket, OF 297 is available for download and can be ordered through the Great Basin Cache.

Beginning January 15, 2026 the previous version of the OF 297 form has been discontinued.

For further details, please contact your IBC representative.

References:

Incident Business Committee Memorandum 26-01

Great Basin Cache

NEW! S-390, Introduction to Wildland Fire Behavior Calculations (Blended) Available Now

Date: December 22, 2025
Questions about RT-130? 
Please contact: Fire Behavior Subcommittee

NWCG is excited to announce that the new S-390, Introduction to Wildland Fire Behavior Calculations (Blended) training is now available on the Wildland Fire Learning Portal.

This third course in the series combines online and instructor-led training components aimed at individuals who are involved in planning, managing, and executing wildland fire and prescribed burn operations; who require a thorough understanding of fire behavior calculations to enhance effectiveness and safety. This includes students who require the knowledge and skill necessary to perform the duties of a Type 3 Incident Commander (ICT3), Division/Group Supervisor (DIVS), or Prescribed Fire Burn Boss Type 2 (RXB2).

Students are required to be qualified as any Single Resource Boss position and complete the prerequisite S-290, Intermediate Wildland Fire behavior (Blended) course, before enrolling in S-390.

References:

S-390, Introduction to Wildland Fire Behavior Calculations (Blended)

Wildland Fire Learning Portal

NEW! S-320, Introduction to Incident Management Teams (Blended) Available Now

Date: December 18, 2025
Questions about RT-130? 
Please contact: Incident and Position Standards Committee

NWCG is excited to announce that S-320, Introduction to Incident Management Teams (Blended) is now available on the Wildland Fire Learning Portal!

This blended course combines online learning with instructor-led training, designed for individuals seeking to build leadership skills and gain experience in incident management.

Students are required to complete the prerequisite trainings ICS-100, Introduction to Incident Command System (ICS), ICS-200, Basic ICS for Initial Response, and ICS-700, An Introduction to the National Incident Management System (NIMS) prior to attending S-320.

References:

S-320, Introduction to Incident Management Teams (Blended)

Wildland Fire Learning Portal