Flash Flood, Severe Weather Threats Through Friday in the Deep South

Tornadoes Are More Powerful Than We Realize

Torrential rain triggered flash flooding in parts of Mississippi Thursday night, particularly in the state capital city.

Over 4 inches of rain flooded streets and parking lots and stranded vehicles in Jackson.

Evacuations of first-floor apartments were prompted on the city's west side as floodwater encroached from the apartment's parking lot.

Thursday was Jackson's second wettest January day on record, in which they picked up almost a month's worth of precipitation.

The Holmes Lake Dam, a small dam in southern Hinds County southwest of Jackson, failed Thursday night damaging a barn, several vehicles and a fence, according to local emergency management.

In southwest Mississippi, a flash flood warning was issued for areas near the Robbins Lake Dam in southern Adams County south of Natchez, where video indicated overtopping of the dam was occurring. According to the National Weather Service, water levels were receding late Thursday night in the dam, but additional rain still could still result in a failure of that dam.

In Natchez, Mississippi, at least five mudslides were reported along Martin Luther King Street. Flooding was also reported throughout Lowndes County, in northeast Mississippi, prompting closures of at least three roads.

Wintertime Severe Weather Not Uncommon in the South

You would think that as it turns colder in the winter, there would be fewer severe thunderstorms.

But that isn't the case in the South.

The northern (polar) jet stream also intensifies during the winter months, which adds to the amount of lift and spin in the atmosphere.

Alabama had 139 January tornadoes in the 69-year period from 1950 to 2018. That's more than occurred in six other calendar months.

Only a couple of weeks ago, severe thunderstorms spawned a tornado outbreak Dec. 16 and 17 across the Deep South from Louisiana to Mississippi, Alabama and Georgia.

NWS damage surveys confirmed over 30 tornadoes in those four states from the outbreak.

Another seven tornadoes were confirmed by the NWS in Mississippi on Dec. 29.

Those two events shattered the December state record for tornadoes in Mississippi and contributed to a yearly state record 114 tornadoes in 2019, according to the NWS.

Episodes of severe weather can continue through the winter from the lower Mississippi Valley into Florida, especially in years when the jet stream is stronger than average.

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