California has experienced severe droughts and wildfires over the past few years. Now it is bracing for significant rain and flooding, with predictions of a bomb cyclone to bring heavy rain to the northern section of the state. But what exactly is a bomb cyclone, and what does it do?

A bomb cyclone is a storm that develops very quickly. When a storm drops in atmospheric pressure very quickly, the storm picks up more air and strength, becoming stronger faster. To be considered a bomb cyclone the pressure must drop 24 millibars in twenty-four hours. The process of this rapid drop in pressure is called bombogenesis. Remember, the lower the barometric pressure, the stronger the storm. Strong storms create large amounts of rain, which can create another problem, flooding.

Wildfires scorch the ground, leaving those areas hard and dry. When rain does come, it tends to run off, creating flash floods. So while rain is much needed, a lot of rain in a short period of time is not as beneficial as it might seem, other than filling reservoirs.