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PMS 437

Fuel Moisture: Vegetative Greenness

Wildland Fire Assessment System (WFAS) AVARR NDVI Greenness Reference is the comprehensive source of images, data archives, and methods for handling.

These images, derived from a satellite sensor, have been produced weekly since 1989, producing a historical record of vegetation phenology that can be used to characterize current vegetation greenness. They can be used to cross-reference with drought assessments and other characterizations of plant development, moisture stress, and curing. Cloud cover can have a significant impact on image quality in portions of the image.

While not an estimate of live fuel moisture, spatial distribution of NDVI estimates and its climatological derivatives can provide important insight to past and current vegetative state and overall landscape flammability during the growing season.

There are several depictions that allow you to evaluate the current NDVI status:

  • Normalized Difference Vegetation Index (ND) is the current derived value from which all the other climatological depictions are derived.
  • Departure from Average Greenness (DA) portrays the absolute difference between current value and the historic average greenness for the corresponding week of the year based on all years 1989-last year.
  • Relative Greenness (RG) portrays how green the vegetation is compared to how green it has been over the historical reference period (1989-last year). Because each pixel is normalized to its own historical range, all areas (dry to wet) can appear fully green at some time during the growing season.
  • Visual Greenness (VG) portrays vegetation greenness compared to a very green reference such as an alfalfa field or a golf course. The resulting image is like what you would expect to see from the air. Normally dry areas will never show as green as normally wetter areas.

This image of Departure from Average Greenness is for September 12, 2011

Departure from Average Vegetative Greenness. Example graphic from the Wildland Fire Assessment System for September 12th of 2011.

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NWCG Latest Announcements

Leadership Committee IAP Flyer Now Available

Date:  May 8, 2026
Questions? 
Please contact: Leadership Committee

The NWCG Leadership Committee promotes and enables leadership development across the wildland fire service. The committee provides education, training opportunities, and support for leadership innovation and best practices throughout the community.

A new IAP flyer is now available on the committee website, offering an overview of the products, curriculum, and learning opportunities the Leadership Committee develops. This resource is ideal for posting in your office, sharing with new employees, or distributing through your incident management teams to engage new voices in the leadership journey and reinforce a culture of self‑reflection, development, and growth.

References:

Leadership Committee 2026 IAP Flyer

Incident Operations Subcommittee Updates the Next Generation Position Task Book for FFT1

Date:  May 7, 2026
Questions? 
Please contact: Incident Operations Subcommittee

The NWCG Incident Operations Subcommittee (IOSC) has updated the NWCG Position Task Book for Firefighter Type 1 (Squad Boss) (FFT1), PMS 311‑14. The FFT1 Position Task Book transitioned to the Next Generation (Next Gen PTB) format in June 2025 through the Incident Performance and Training Modernization effort. Since then, IOSC has received feedback from the wildland fire community regarding coding for one of the tasks. Task #13 has been updated to include the option of evaluation in a simulation.

See IOSC Memorandum 26‑01: Transition Plan for Implementation of Updates to the NWCG Position Task Book for Firefighter Type 1 (Squad Boss) (FFT1), PMS 311‑14 for more information.

References:

IOSC Memorandum 26-01: Transition Plan for Implementation of Updates to the NWCG Postion Task Book for Firefighter Type 1

NWCG Firefighter Type 1 Squad Boss Position Page 

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