Mesoanalysis on the morning of July 24th, revealed multiple boundaries across Central Alabama and in the vicinity. Radar and satellite indicated several old outflow boundaries and differential heating boundaries were in place across the northeast half of the forecast area (see loop below). These boundaries were the primary mechanism by which convection initiated late that morning. Once convection was ongoing, outflow boundary collisions provided additional focus for thunderstorm development.
The localized flooding in and around the Tarrant and Birmingham Airport areas was the result of boundary/storm collisions, heavy rainfall, poor drainage and excessive runoff in the urban areas, and flashy creeks. Thunderstorms along a boundary moved south toward the airport and merged/collided with another storm near Irondale. This collision led to additional development and intensifying rainfall amounts. The nearly stationary storms dropped 2-3 inches of rain in just one hour. Storm total rainfall amounts of 3-4 inches were noted, with the Birmingham Airport reporting a total of 3.64 inches for the day. Significant flash flooding occurred along Hwy 79 in downtown Tarrant and along several streets near the airport, including Tallapoosa Street. and 14th Ave N. Several vehicles were stranded in the floodwaters. Much of the flooding was due to Fivemile Creek and Village Creek overflowing their banks. Thankfully, no injuries or deaths occurred.
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