The four hurricanes that crossed the Sunshine State in August and September 2004 dumped as much as 27 inches of rain (nearly double the regular amount of rain) in central Florida. All that rain increased the amount of pollution that flowed on the earth’s surface and into rivers and the ocean (called runoff). It may also have increased the amount of groundwater (water that flows underground) because some was absorbed into the ground. These two things are thought to create conditions needed for the bloom of red tide.