New Zealand Seasonal Fire Danger Outlooks

Each summer Scion prepares fire danger outlooks for Fire and Emergency New Zealand. Outlooks are produced each month over the fire season for both of the North and South Islands. The purpose of these monthly outlooks provide a heads up on progressing fire danger conditions as we transition from spring to summer, and then into autumn.

The reports enable fire agencies to prepare in advance for changes in fire danger conditions in their area. They are used as a prompt for local and regional discussions on fire potential (which depends on a number of other factors in addition to weather and climate effects, including fuel conditions (i.e. grass curing), risk of ignitions, recent fire history and fire management resource availability).

An outlook is produced for each Island monthly. The preparation of each report includes analysing current and historical fire danger conditions, interpreting NIWA and MetService climate outlooks, and determining likely impacts on the potential for wildfires in different regions of the country.

Comparisons of fire danger for individual indicator stations in different regions of the country are also available as graphs. Trends for the Drought Code (DC), Buildup Index (BUI) and Cumulative Daily Severity Rating (CDSR) are provided for all stations in PDF format.
The more detailed regional graphs highlight where the BUI, DC and CDSR values sit in comparison with previous fire seasons. The graphs display:

  • The current fire season (bold red line)
  • The long-term average (bold black line)
  • The range of historical max and min values (light grey shaded area)
  • Similar fire season years based on ENSO status - which for the current 20/21 fire season is 2010/11, 2007/08, 1999/00, and 1998/99 (moderate strength La Niña event) and 2011/12 (weak La Niña event). These years are potentially good indicators for what to expect this coming fire season.

Tracking trends in BUI, DC and CDSR

This tool provides a visual summary of current and historical trends on a daily basis for fire managers. The graphs below track the Drought Code (DC), Buildup Index (BUI) and Cumulative Daily Severity Rating (CDSR) from fire weather stations nationwide. This allows you to compare fire danger at individual stations in any given region or across the country.

The options include plotting the current year and selected individual years against the historical range of a given weather station with one station per graph, or plotting historical average or current year data for multiple stations on one graph.

The plots can be viewed online or saved as a PDF file. There is also an option for downloading all the plots grouped by region as multiple PDFs.