Flash Flood in Pearl River County, Mississippi

Picture of water flowing over the street and at least one truck inundated with water in Westchester subdivision.

A mesoscale convective system formed on the eastern side of Post-Tropical Storm Arthur on June 18th. Favorable low level winds allowed for multiple mini-supercells to form on the leading edge of the mesoscale convective system resulting in a few tornadoes affecting coastal Mississippi. These tornadoes were rated as EF-0 and EF-1 events. A bow echo also developed over coastal Mississippi leading to severe winds and thunderstorm wind damage in the Gulfport-Biloxi metro area. Additionally, the mesoscale convective complex tapped into a region of deep tropical moisture with atmospheric moisture content well above normal levels for mid-June. This resulted in several significant flash flooding events in portions of coastal Mississippi including the city of Picayune. Two fatalities occurred near Picayune where rainfall rates of 2 to 3 inches per hour and QPE of 10 to 15 inches was noted. This very high rainfall total resulted in major flooding on the West Hobolochitto Creek on June 18th and this is where the fatalities occurred. Lingering moisture and weak upper level troughing associated with the slow moving remnants of Post-Tropical Storm Arthur produced additional thunderstorm activity on June 20th. This activity was focused in Biloxi where additional flash flooding occurred.