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Fire Danger Background

  1. General References
  2. NFDRS Version Comparison

General References

Fire Danger ratings are an effective part of daily risk rating and operational preparedness for fire management agencies across the world. Chapter 10 – Preparedness of the Interagency Standards for Fire and Fire Aviation Operations outlines processes and resources applied in the development of standard Fire Danger Operating Plans in the United States.

Included in Fire Danger Operating Plans are:

  • Specification of fire danger ratings.
  • Identification of climatological thresholds for administrative purposes. Default thresholds include the 90th and 97th percentile values for key indices in the applied system. The Bureau of Land Management (Department of Interior) uses the 80th and 95th percentiles instead.
  • Communication of those danger ratings, including both internal and external forms.

Some valuable links:

A variety of fire weather systems are applied in danger rating around the United States. There are primarily two systems used in fire danger operating plans.

U.S. National Fire Danger Rating System (NFDRS):

First introduced in 1964, NFDRS has been updated in 1972, 1978, 1988, and now 2016 to integrate newer science and improved processing. This guide will compare important aspects of the 1978, 1988, and 2016 versions, detail important outputs, and describe primary components and indices. More information about the system and the latest update to it can be found at:

NFDRS Information Page

NWCG Fire Danger Subcommittee Website

The Canadian Forest Fire Danger Rating System (CFFDRS) Fire Weather Index (FWI) System

CFFDRS was introduced in Canada in 1970. Implemented in Alaska and the lake states of Michigan,
Minnesota, and Wisconsin in the early 1990s. Details about CFFDRS are included a separate section of this guide. The following websites provide data access:

Other tools, formulations, and applications are used locally across the country. Some examples are highlighted later, in the  Fire Danger References Section.

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NFDRS Structure

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Structure and Process Flow of the 2016 National Fire Danger Rating System.

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NWCG Latest Announcements

2024 Wildland Fire Emergency Medical Service Awards

Date: May 22, 2025
Questions?  Please contact:
Emergency Medical Committee

The NWCG Emergency Medical Committee (EMC) is proud to announce the recipients of the 2024 Wildland Fire Emergency Medical Service Awards. Each year, EMC recognizes individuals and groups who have demonstrated exceptional actions or accomplishments that go above and beyond their normal mission or job duties.

Congratulations to all the awardees and nominees. Through leadership and initiative, they have made significant contributions to the safety and well-being of the wildland fire community. These honors are well deserved.

References:

2024 Wildland Fire EMS Awards

NWCG Emergency Medical Committee

NWCG Welcomes the Incident Management Teams Association as an Associate Member

Date: May 21, 2025
Questions?  Please contact:
https://www.nwcg.gov/contact-us

The NWCG Executive Board is honored to announce that the Incident Management Teams Association (IMTA) has joined the National Wildfire Coordinating Group as an associate member.

IMTA is a dedicated group of incident management professionals committed to enhancing the profession by promoting standards and fostering collaboration across federal, state, local, Tribal, and private sector partners throughout all phases of incident management.

“Joining NWCG aligns with our mission to elevate incident management professionals nationwide,” said Dr. Randal Collins, President of IMTA. “This is a proud moment for all of us committed to advancing public safety.”

References:

Incident Management Teams Association

National Wildfire Coordinating Group

Updated NWCG Guide for Wildland Fire Modules, PMS 431

Date: May 14, 2025
Questions?  Please contact:
Fire Use Subcommittee

The updated NWCG Guide for Wildland Fire Modules, PMS 431 serves as a supplemental resource for wildland fire module operations, providing information frequently used in the field.

PMS 431 defines the organizational structure, staffing, and qualifications for Type 1 and Type 2 Wildland Fire Modules, outlining their roles in wildland fire suppression, prescribed fire, and resource management. The NWCG Guide for Wildland Fire Modules, PMS 431, should be used in conjunction with the NWCG Standards for Wildland Fire Module Operations, PMS 430.

References:

NWCG Guide for Wildland Fire Modules, PMS 431

NWCG Standards for Wildland Fire Module Operations, PMS 430

Updated NWCG Standards for Wildland Fire Resource Typing, PMS 200 Now Includes Off-Highway Vehicle Typing Standards

Date: May 13, 2025
Questions?  Please contact:
Mobile Fire Equipment Subcommittee 

The NWCG Standards for Wildland Fire Resource Typing, PMS 200 has been updated to include newly developed Off-Highway Vehicle (OHV) typing standards. These standards organize OHV information into logical categories and outline key safety requirements for occupants.

NWCG Standards for Wildland Fire Resource Typing, PMS 200 establishes minimum typing standards for aircraft, crews, and equipment used in national mobilization to wildland fire incidents. Typing designations are assigned based on measurable capability and performance criteria.

References:

NWCG Standards for Wildland Fire Resource Typing, PMS 200