Fire Danger Information

Extreme Fire Danger

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Any outbreak of fire is extremely serious

All fires are potentially serious and will easily become uncontrollable, unpredictable and fast moving.

These fires are very difficult to fight and may become very dangerous and often last for several days.

Very High Fire Danger

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Outbreak of fire is very serious

Fires will start easily and will spread rapidly and burn intensely right after ignition.

Small fires can quickly become large fires and show extreme fire behaviour.

These fires can be difficult to control and will often become much larger and longer-lasting fires.

High Fire Danger

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Outbreak of fire is serious

Fires can start easily and control becomes increasingly more difficult the longer the fire is left.

Moderate Fire Danger

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Control of fires is reasonably easy

Fires are not likely to become serious and are often easy to control if attended to quickly.

Low Fire Danger

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Wildfires are unlikely

Ignition may take place near large and prolonged heat sources but the resulting fires generally do not spread much.

Control of fires is generally easy.

Fire Weather Index Definitions

FFMC - Fine Fuel Moisture Code

Material: Cured (dead) small material e.g. pine needles, dead grass

Indices: Indicates the relative ease of ignition and flammability of fine fuels

How Does it Change: FFMC changes by the hour and is affected by as little as 0.6mm of rainfall

Points of Interest on Graph:

  • 75 - Ignition can occur
  • 85 - Easy ignition
  • 92+ - Extremely easy to ignite

DMC - Duff Moisture Code

Material: Medium material e.g. branches, small trees, scrub, and forest duff layer

Indices: Indicates the depth a fire will burn and how much medium fuel will be consumed

How Does it Change: DMC changes by the day, it is affected by >= 1.5mm of rainfall

Points of Interest on Graph:

  • 20 - Some burning will occur
  • 40+ - Deep burning will occur

DC - Drought Code

Material: Large Material e.g. logs, subsurface fuels, and peat soils

Indices: Indicates depth of burning & smouldering in large material and seasonal drought effects in forest fuels

How Does it Change: DC changes by the day and is affected by >= 2.9mm of rainfall

Points of Interest on Graph:

  • 200 - Large material will start to burn and some deep smouldering will occur
  • 300+ - All large and sub surface material will burn easily

ISI - Initial Spread Index

What does it Tell Us: Determines the expected rate of fire spread shortly after ignition

How: Combines the effects of wind and Fine Fuel Moisture Code (FFMC) to determine the rate of spread

What is the Scale it is Measured on: zero to infinity

Points of Interest on Graph:

  • 10 - Fast rate of spread
  • 16+ - Extremely fast rate of spread

BUI - Build Up Index

What does it Tell Us: Amount of fuel available to burn and the level of difficulty in controlling a fire

How: Total amount of fuel available for combustion is measured by calculating the Duff Moisture Code and Drought Code

What is the Scale it is Measured on: zero to infinity

Points of Interest on Graph:

  • 40 - High level of fuel becomes available for combustion
  • 60+ - All fuels available to burn and extremely difficult fire to control

FWI - Fire Weather Index

What does it Tell Us: Indicates the likely intensity a fire will burn at and is used to indicate fire danger levels

How: Combines Initial Spread Index and Build Up Index

What is the Scale it is Measured on: zero to infinity

Points of Interest on Graph:

  • 0-5 - Low
  • 6-12 - Moderate
  • 13-20 - High
  • 21-29 - Very High
  • 30+ - Extreme

Notifications for Otago Rural Fire District

Restricted Fire Season
Restrictions are placed on some burning activities because vegetation dries out due to wind, low humidity and warm days, increasing the risk of wildfires occurring.
You may still be able to have a fire provided you obtain a Fire Permit. Contact your rural fire authority to find out if you require a Fire Permit.

Please be aware that some areas within this district are under the Southern Rural Fire Authority jurisdiction. If your area is blank on the map then please navigate to the SRFA page for appropriate fire danger levels and contact information.