Fire Weather Warnings

Introduction

Wind, temperature, humidity and rainfall are weather elements that  affect the behaviour of bushfires. In Australia there is a system of assessing these in conjunction with the state of the available fuels to determine a measure of "fire danger", or the difficulty of putting out any fires which may occur. The Bureau of Meteorology issues products that alert the public when conditions are likely to be dangerous - Fire Weather Warnings and Total Fire Ban Advices.

Changes to Fire Weather Warnings and Forecasts from October 2009

The Bureau of Meteorology has incorporated changes to the Fire Danger Ratings used by fire agencies in its weather forecasts and warnings.

What's changed?

The Extreme category has been divided into three levels - Severe, Extreme and Catastrophic (Code Red). These new levels are based on the Forest Fire Danger Index (FFDI) and the Grass Fire Danger Index (GFDI).

The new Fire Danger Ratings.

• Severe fire danger will be indicated when FFDI/GFDI is between 50 and 74;
• Extreme fire danger will be indicated when FFDI/GFDI is between 75 and 99; and
• Catastrophic (Code Red) fire danger will be indicated when FFDI/GFDI is 100 or above.

Due to software constraints and accessibility requirements, the Bureau of Meteorology uses slightly different colours for Fire Danger Rating. Refer to the table below.

 

Note:

In Western Australia the threshold between High and Very High will remain at FDI = 32 Catastrophic fire danger will be indicated by the colour black in Tasmania

Fire Weather Warnings

The Bureau's fire weather services have been developed in close consultation with the fire authorities in each State and Territory to best cater for local requirements. We issue Fire Weather Warnings when the rating on the fire danger scale is expected to exceed  thresholds agreed to with fire agencies. This is usually assessed over either Bureau  weather forecast districts  or over  areas specified by fire agencies (such as  in New South Wales).
The information contained in a fire weather warning will be:

• The office which issued the warning
• The local time, day and date that it was issued
• A description of the relevant meteorological conditions and fire danger
• The area affected
• The time period for which it will be in effect

We also include a total fire ban message if a ban is in force and an action statement where the local fire authorities have provided one.
Fire Weather Warnings are distributed through the media and to fire agencies and other key emergency services organisations. They are normally issued in the afternoon for the following day so that they are available in time for the evening television and radio news services. However, they may be issued at any time that the need is recognised. They are renewed at regular intervals, generally at major forecast issue times, and amended immediately if the need is recognised. If there is a Fire Weather Warning current we will mention this in State/Territory and District weather forecasts for that area.
In each State the issue of a Fire Weather Warning has different impacts on restrictions for lighting fires. Check with the fire authority and / or local council in your area for details.
Sample Fire Weather Warning

Total Fire Bans

The Bureau of Meteorology doesn't have the power to declare a Total Fire Ban. This responsibility resides with designated fire agencies in each State and Territory, however in South Australia, the Northern Territory , Victoria, New South Wales and Tasmania we issue fire ban advices to assist in publicising them. We also include the existence of fire bans, when they are current, in our weather forecasts and warnings.
The areas covered by Fire bans do not align with Bureau forecast districts in Victoria, New South Wales, Tasmania and the Northern Territory You should check  with your fire authority and / or local council about fire ban boundaries and  the impact of a  Total Fire Ban is in your area.
Sample Fire Ban Advice