With current dry conditions being experienced in some areas of the province, AAMDC is reminding members of an Agriculture and Forestry information resource, which produces fire weather indices maps to identify fire potential and monitor conditions in the white zone of the province. The indices used on these maps include Fine Fuel Moisture Content (FFMC) and Initial Spread Index (ISI).
The FFMC is a numeric rating of the moisture content of grass, crops, and other fine fuels and is an indicator of their ease of ignition. The FFMC is determined using temperature, relative humidity, wind speed, and 24-hour rainfall. The moisture content of the fine fuels is very sensitive to the weather, even a day of rain or wind will have a significant effect on the FFMC rating. This rating is on a scale of 0-99 and any figure above 85 is high and above 92 is extreme.
The ISI is a numeric rating that identifies the rate the fire will spread in its early stages and is calculated from the FFMC and wind speed. The ISI scale starts at zero, a rating between 5 and 9 indicates a high rate of spread shortly after ignition. A rating of 16 or more indicates extremely rapid rate of spread.
The maps are housed on the Alberta Climate Information Service
(ACIS) website, and available directly by clicking here
As a result of dry conditions these maps are currently generated on a daily basis using data from 350 weather stations in Alberta. The maps can be used daily to aid municipalities in assessing the probability of a fire starting, spreading and causing damage.
Enquiries may be directed to:
Director, Advocacy & Communications