When taking Fire damage a unit may catch fire, which will subject it to additional burning damage until the fire goes out.

A unit that is burning takes 1d(size) damage each turn until the fire goes out (a die with a number of sides equal to the size of the unit, so for a Size 6 unit it would be 1d6). The chance of the fire going out is

All fire have a minimum 1% chance of being extinguished. If the province has heat scales instead, this is treated as negative cold.