Haines Index is a weather index developed by meteorologist Donald Haines in 1988 that measures the potential for rapid forest fire growth. The index is derived from the stability (temperature difference between different levels of the atmosphere) and moisture content (dew point depression

Dew point depression

The dew point depression is the difference between the temperature and dew point temperature at a certain height in the atmosphere....

) of the lower atmosphere

Atmosphere

An atmosphere is a layer of gases that may surround a material body of sufficient mass, and that is held in place by the gravity of the body. An atmosphere may be retained for a longer duration, if the gravity is high and the atmosphere's temperature is low...

. These data may be acquired with a radiosonde

Radiosonde

A radiosonde is a unit for use in weather balloons that measures various atmospheric parameters and transmits them to a fixed receiver. Radiosondes may operate at a radio frequency of 403 MHz or 1680 MHz and both types may be adjusted slightly higher or lower as required...

. The index is calculated over three ranges: low elevation (950-850mb

Bar (unit)

The bar is a unit of pressure equal to 100 kilopascals, and roughly equal to the atmospheric pressure on Earth at sea level. Other units derived from the bar are the megabar , kilobar , decibar , centibar , and millibar...

), mid elevation (850-700mb), and high elevation (700-500mb).

A Haines index of 6 means a high potential for large fire growth. 5 means medium potential, 4 low potential, and anything less than 4 means very low potential.

See also

• Fosberg index
• Forest fire weather index
• Wildfire modeling
  Wildfire modeling
  In computational science, wildfire modeling is concerned with numerical simulation of wildland fires in order to understand and predict fire behavior. Wildfire modeling can ultimately aid wildland fire suppression, namely increase safety of firefighters and the public, reduce risk, and minimize...