Storm damage in Riverview from Thursday

Looks like a microburst occurred in Riverview yesterday as a very strong outflow boundary collided with another developing severe storm. I actually watched this as it occurred, for a brief moment it looked as if a brief tornado could have developed as there was a small compact area of rotation along the outflow boundary. Turns out it was just a small microburst that damaged roofs and uprooted trees. The statement from the weather service in Ruskin is below:

During the afternoon of June 18, 2009, a line of strong thunderstorms moved south colliding with other thunderstorms developing along the west coast sea breeze (see radar loop below). When this collision occurred the storms became severe over Riverview producing a downburst. Downbursts are generated when rain-cooled, dense air sinks inside a thunderstorm. Also, some of the strong winds aloft are carried down with the downburst by a process called “momentum transfer”. As precipitation begins to fall, it drags some of the air with it. This “precipitation drag” initiates a downburst. The downburst is intensified by evaporative cooling as drier air from the edges of the storm mix with the moist air within the storm. Downbursts are divided into two categories, macrobursts and microbursts. A macroburst is more than 2.5 miles (4 km) in diameter while microbursts are smaller. Based on the NWS survey this event would be defined as a microburst.