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PMS 425

PMS 425

PMS 425

NWCG Guide to Fire Weather Forecasts PMS 425

1. Introduction

2. Fire Weather Forecast Variables

3. Types of Fire Weather Forecasts

4. Building a Mental Model of the Weather Forecast

1. Introduction

Fire weather forecasts are likely one of the first professional introductions firefighters have to meteorological information. They may even be the first thing a firefighter reads each day when they get to their duty station. Forecasts convey certain atmospheric variables. The intent of this guide is to describe best-practices on how to interpret and use the weather information provided.

Fire weather forecasts include several components:

  • Header information
    • Date and time the forecast is valid for
    • Applicable forecast headline
  • Forecast discussion
  • Mandatory forecast elements of sky/weather
    • Temperature
    • Relative humidity (RH)
    • Wind
  • Optional forecast elements that may include the chance of:
    • Wetting rain
    • Mixing height
    • Transport wind
    • Smoke dispersal
    • Inversion information
    • Haines Index
    • Lightning activity level (LAL)
    • Extended forecast or outlook

Each forecast element is generally given only one value per operational period.

The weather forecast is a static document that may not adequately describe the changes one sees in the weather through an operational period. For example, fire weather forecasts only provide the high temperature for day operational periods and the low temperature for night operational periods. It is left up to the firefighter to interpret how fast and when the temperature will rise and/or fall during their shift. Consistent weather is a firefighter’s friend. It is the change in weather conditions that prove problematic and sometimes fatal to operational resources. This publication provides context and interpretation guidelines for fire managers and fireline personnel to make improved decisions with safety in mind.

There are links to online resources throughout this publication. Visit these resources, as additional information and graphics are often provided. The most frequently linked resource is the Agriculture Handbook 360: Fire Weather… A Guide for Application of Meteorological Information to Forest Fire Control Operations, PMS 425-1. Refer back to it as you learn more about fire weather forecasts.

Modified / Reviewed:

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NWCG Latest Announcements

The Incident Position Standards and Next Generation Position Task Book are now available for Status/Check-In Recorder (SCKN)

Date: August 27, 2024
Contact: Incident Planning Subcommittee 

NWCG is excited to announce that the NWCG Incident Position Standards for Status/Check-In Recorder, PMS 350-32, NWCG Position Task Book for Status/Check-In Recorder (SCKN), PMS 311-32, and Checking In Resources Customer Service Job Aid, J-111 are now available.

The Performance Support Package, which for SCKN includes the Incident Position Standards, Next Generation Position Task Book, and job aid were developed through the Incident Performance and Training Modernization (IPTM) effort. The Performance Support Package will support trainees, those qualified in the position, and evaluators.

References:

NWCG Status/Check-In Recorder Position Page

NWCG Incident Position Standards for Status/Check-In Recorder, PMS 350-32

NWCG Position Task Book for Status/Check-In Recorder (SCKN), PMS 311-32

Checking In Resources Customer Service Job Aid, J-111

The Next Generation Position Task Book and Incident Position Standards are now available for Safety Officer, Field (SOFF)

Date: July 26, 2024
Contact: Risk Management Committee 

NWCG is excited to announce that the NWCG Incident Position Standards for Safety Officer, Field, PMS 350-81 and NWCG Position Task Book for Safety Officer, Field (SOFF), PMS 311-81 are now available.

The Safety Officer, Field (SOFF) is responsible for monitoring operations on an incident from a risk management perspective to provide for the welfare of incident resources and the public. The new Incident Position Standards and Next Generation Position Task Book are developed through the Incident Performance and Training Modernization (IPTM) effort.

References:

NWCG Safety Officer, Field (SOFF) Position

NWCG Incident Position Standards for Safety Officer, Field, PMS 350-81

NWCG Position Task Book for Safety Officer, Field (SOFF), PMS 311-81

Updated NWCG Standards for Electronic Documentation (eDoc), PMS 277

Date: July 25, 2024
Contact: Incident Planning Subcommittee 

The Incident Planning Subcommittee has updated the NWCG Standards for Electronic Documentation (eDoc), PMS 277.

The NWCG Standards for Electronic Documentation (eDoc) establishes the standards for collection and retention of records on wildland fires. This July 2024 update will provide incident management teams the most current standards required to maintain incident records and submit them to host units at the close of an incident.

References:

NWCG Standards for Electronic Documentation (eDoc), PMS 277

eDoc Box Directory (zip file)

NWCG Off-Highway Vehicle Typing Standard Request for Comment

Date: July 24, 2024
Contact: Mobile Fire Equipment Subcommittee 

The Mobile Fire Equipment Subcommittee has released Equipment Bulletin 24-002 NWCG Off-Highway Vehicle (OHV) Typing Standard - Request for Comment. This bulletin outlines the proposed NWCG OHV typing standard, as well as the business need for establishing the standard. Comments on the proposed standard will be accepted through August 15th using the comment form linked below.

References:

ETC-EB-2024-02: NWCG Off-Highway Vehicle (OHV) Typing Standard - Request for Comment

NWCG Off-Highway Vehicle (OHV) Typing Standard Comment Form