Drenching storm to cause flooding, travel issues in southeastern US through midweek

Following a quick blast of Arctic air, a slow-moving storm will drench the southern United States and raise the risk of localized flooding spanning Tuesday night to Thursday of this week.

In addition to travel problems associated with the rain, a temperature roller coaster is in store this week.

Arctic air in place at the start of the week over the Eastern states is forecast to pick up and leave. Temperatures will trend upward by 20 degrees Fahrenheit or more from Monday to Wednesday.

For example, in Atlanta, after a high of 44 on Monday with early morning temperatures in the 20s, temperatures may top 60 on Wednesday.

Rain is forecast to advances eastward during the middle days of the week. A general 1 to 1.50 inches of rain is forecast with local amounts between 2 and 3 inches.

Rain is forecast to break out on Tuesday over the lower portions of the central and southern Plains to the lower Mississippi Valley. This rain will pick up in intensity during Tuesday night.

On Wednesday and Wednesday night, the rain will advance eastward across the Tennessee Valley and central Gulf coast to part of the southern Appalachians.

During Thursday, the rain will focus from the Piedmont areas to the southern Atlantic and northeastern Gulf coast regions.

As the rain enters the southern Appalachians, where pockets of chilly air and cold surfaces remain, there is the risk of icy areas for a time on Wednesday.

Since much of this rain may fall in 12 hours or less, there is the potential for street, highway and other urban-style flooding.

Areas of fog and breezy conditions are also in store with the storm.

The combination of rain, fog and a breeze can make for poor travel on the roads and lead to airline delays.

A few locally strong thunderstorms may develop in the Interstate 10 and 20 corridors and over the Florida Peninsula. The main risks from the storm will be for flash flooding and brief gusty winds. However, a brief spin-up tornado cannot be ruled out.

In the immediate wake of the storm, cooler air will settle in on Wednesday over the South Central states and Thursday to Friday over the Southeast.

However, another batch of Arctic air will follow from Thursday to Friday over the South Central states and Friday to Saturday over the southeastern corner.

Temperatures are likely to plunge 20 degrees after the midweek surge.

Highs within a few degrees of 40 and lows in the 20s are in store for Atlanta on Friday.