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Replacing Haines Index and Lightning Activity Level

Background

The National Wildfire Coordinating Group (NWCG) Fire Weather Subcommittee (FWS) has recommended discontinuing the use of Haines Index (HI) and Lightning Activity Level (LAL) in fire weather forecasts and in NWCG training and curricula. A transition plan has been built to help firefighters understand what weather metrics to assess and how to brief all levels in the chain of command for the 2025 fire season.

Why are these fire weather metrics being replaced?

The HI is unsupported by research in predicting large fire growth and it is not a metric of atmospheric stability. Additionally, LAL is a duplicate of the thunderstorm coverage product that is already in the fire weather forecasts. The decision process included extensive interagency coordination and discussion as well as evaluation of peer-reviewed research.

Mixing Height

  • Mixing Height is the best current metric to replace HI.
  • Answers the question: how high in the atmosphere will rising air (fire column/smoke) ascend freely.
  • Mixing Height and Mixing Depth are interchangeable terms.
  • Mixing Height can indicate the ability of the atmosphere to support ascent of smoke and fire columns and conversely, resistance to vertical motion.
  • WHERE TO FIND: Spot Weather Forecast Discussions, Fire Weather Forecast discussions, and Fire Weather Dashboard (limited to 72 hours).

Mixing Height graph 72 hour limit.

Chance of Precipitation Crosswalk

  • Combining working in the Chance of Precipitation and Chance of Wetting Rain are the best resources (combined) to replace LAL.
  • Assessing the Potential for Lightning:
    • Are thunderstorm chances (in %) given in Sky/Weather section?
    • A higher percentage means higher odds for storms and lightning.
    • Compare to Chance of Wetting Rain (CWR). A high thunderstorm chance with low CWR may imply dry thunderstorms.
    • Remember any thunderstorm can lead to ignitions from lightning.
  • WHERE TO FIND: Chance of Precipitation and Chance of Wetting Rain from Fire Weather Planning Forecast, Spot Weather Forecast, and Fire Weather Dashboard.

References:

Category
Weather - Fire Behavior

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NWCG Latest Announcements

NEW! S-212, Intermediate Faller (Online) Course Available Now 

Date:  April 23, 2026
Questions? 
Please contact: Hazard Tree and Tree Felling Subcommittee

NWCG is pleased to announce that the new S‑212, Intermediate Faller (Online), course is now available on the Wildland Fire Learning Portal (WFLP). This second course in the series provides students with the knowledge and skills required to perform the duties of an Intermediate Faller (FAL2), as described in the FAL2 Incident Position Description. This course is intended for individuals seeking to advance from Basic Faller (FAL3) to FAL2.

S‑212, Intermediate Faller is a fully online, self‑paced training program consisting of 13 units. Learners will engage with interactive, scenario‑based content designed to progressively build foundational skills and knowledge essential for the FAL2 role.

Students must be qualified as a Basic Faller (FAL3) prior to enrolling in S‑212, Intermediate Faller course.

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 2027.

References:

S-212 Intermediate Faller (Online)

RMC Memo 26-01: Transition Plan for Implementing Updates to Intermediate Faller (FAL2) Position Qualifications

Intermediate Faller (FAL2) Position Page

NWCG Standards for Wildland Fire Chainsaw Operations, PMS 212

New Aircraft Flight Schedule Form, PMS 249

Date:  April 17, 2026
Questions? 
Please contact: National Coordination System Committee

A new publication from the National Coordination System Committee (NCSC) is now available. The NWCG Aircraft Flight Schedule Form, PMS 249, will be used for aviation crews and dispatch to share flight information that is needed for resource tracking, and if needed, for emergency procedures.

For further details, please contact your NCSC representative. 

References:

NCSC Memo 26-01: Implementation of NWCG Aircraft Flight Schedule Form, PMS 249

NWCG Aircraft Flight Schedule Form, PMS 249

New Glossary Term for Review

Date:  April 15, 2026
Questions? 
Please contact: Data Standards and Terminology Board (DSTB)

The Data Standards and Terminology Board is requesting feedback on a new glossary term: Resource Protection Measure (RPM).

The proposed definition is: Practical guidance provided for incident personnel in a manner in which incident objectives can be achieved while reducing impacts to identified resources across the landscape. RPMs are informed by, but not restricted to, Minimum Impact Strategies and Tactics (MIST).

Please review, share with your subgroups, and provide feedback as appropriate through the following form: Request Feedback The comment period will close May 10, 2026.

Thank you for your engagement in the NWCG glossary process – your participation is key to our success.

References:

Glossary Request Feedback

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