Drought code

Essentially, it's a measure of how dry the deeper, heavier fuel layers are, reflecting prolonged dry periods and the potential for deep-seated, long-burning fires.

The drought code is heavily influenced by:

• Prolonged dry periods: The drought code accumulates the effects of extended periods without significant rainfall. It reflects the cumulative drying of deeper fuel layers.
• Temperature: Higher temperatures over extended periods contribute to a higher drought code by increasing evaporation and reducing deep fuel moisture.
• Lack of significant precipitation: The drought code is not significantly affected by short-term rainfall. Only prolonged, substantial precipitation will significantly reduce it.
• Time: The drought code is a slow-responding index, meaning it takes a long time for it to change. It is an indicator of long term dryness.

The drought code is a key indicator of the potential for deep-seated fires that can persist for long periods, even in seemingly moist conditions. It helps predict the likelihood of large, intense fires that can consume heavy fuels and create significant smoke. It is a good indicator of the amount of effort that will be needed to extinguish a fire, as high drought codes mean that very deep burning can occur.

The drought code is a crucial component of fire weather index systems. It provides a long-term assessment of the dryness of heavy fuels, allowing fire managers to predict the potential for prolonged, intense fires. A high drought code indicates a greater risk of these deep-burning, long-lasting fires, while a low drought code suggests a lower risk.