AccuWeather forecasters say the storm will cause numerous delays for vacationers and Black Friday shoppers in the South as hazards like local flooding develop over the bank holiday weekend. File Photo by Anthony Stalcup/UPI | license photo

The southern, central and southeastern parts of the United States are expected to bear the brunt of the impact of a giant cross-country storm that begins Thanksgiving and lasts through the holiday weekend.

AccuWeather forecasters say the storm will cause numerous delays for vacationers and Black Friday shoppers as hazards like local flooding develop over the bank holiday weekend.

An upper-level storm, the first component of the Great Thanksgiving Storm, will sweep across the western United States by mid-week. As it meets moisture streaming north from the Gulf of Mexico, a major storm will form over the southern plains and Mississippi Delta region on Thanksgiving Day.

“As the storm develops Thursday through Friday, bouts of rain will fill some rain gauges in the lower Mississippi Valley and Southeast, perhaps on the order of 2 to 4 inches, particularly from east Texas to north Georgia, South Carolina state and western North Carolina ‘ said AccuWeather’s chief weather forecaster, Bill Deger.

Local precipitation of up to 6 inches is most likely from northeast Texas to northern Louisiana and northwest Mississippi.

“Due to the region’s drought conditions and low water levels in most rivers, lakes and reservoirs, the rain is not necessarily undesirable, but the timing will be ill-timed as it arrives just in time for the holiday and will impact some outdoor plans and travel ‘ Deger said.

Motorists may encounter poor visibility and excessive water on the roads in the Interstate 10, 20, and 40 corridors. Weather conditions and traffic could be a dangerous combination given the volume of vehicles on major freeways and secondary roads. AccuWeather forecasters advise that people allow extra time to get to their destinations and be aware of poor road conditions and the possibility of water accumulation on roads while driving.

Most of the rain will fall around Dallas and Houston from Wednesday night into Friday. In the zone from New Orleans to Shreveport, La., the worst travel conditions prevail from Thursday to Friday night.

Farther east, a more pronounced double amount of rain is likely to occur as one storm system moves away and another forms and gains momentum.

For example, in the Atlanta area, the first primary dose of torrential rain is forecast for Thursday night.

“But, a A large round of precipitation will follow Saturday night in Atlanta and much of the busy I-85 corridor, and that will likely cause travel delays,” said AccuWeather chief meteorologist Bernie Rayno.

AccuWeather forecasters say people shopping on Small Business Saturday should be aware of another hazard. Thunder and lightning may accompany rain in the southeast on Saturday. There may also be some locally severe and gusty storms breaking out. AccuWeather forecasters will continue to monitor the situation for severe weather hazards.

For those spending their Thanksgiving long weekend at Central Florida’s theme parks, there are Friday and Saturday highs in the 80s. Thunderstorms are expected across Florida on Friday, while there will be occasional showers on Saturday.

Multiple rainstorms in recent weeks from the Gulf Coast to the Ohio Valley have caused water levels along the Mississippi to rise regularly. Although most of the rain from the upcoming storm will be concentrated in the delta region, it should raise water levels on the waterway briefly and possibly spur shipping traffic for a while.

A cool wedge of air should be enough to keep large-scale severe thunderstorms in check with this system until Friday.

“However, some robust thunderstorms may break out along the northwestern Gulf Coast on Thanksgiving Day and over the north central Gulf Coast on Friday,” said Adam Douty, AccuWeather’s chief weather forecaster. “Some of these storms can be quite violent and gusty.” There is a chance for storms to become severe right along the I-10 corridor.

At this time, AccuWeather forecasters are emphasizing the risk of torrential downpours in the region but remain concerned about more intense storms near the Gulf.

However, the storm could grow strong enough on Saturday to bring last-minute severe weather to the southeastern states. “There will be at least some risk of severe weather late Saturday through Saturday night from the coast of South Carolina to South Georgia,” Rayno said.

The storm will have a cold side and that could put some at risk of some winter weather effects.

As the storm intensifies, just enough cold air will be drawn in on its northwestern flank to create a patch of heavy, accumulating snow in the Texas and Oklahoma Panhandles and eastern New Mexico by later Thanksgiving through Friday night and perhaps early Saturday .

A general 6-12 inch snowpack will cover northwest Texas and part of eastern New Mexico.

Despite the snow for the southern High Plains, the storm is not expected to be followed by a massive cold draft over the south-central and south-eastern states, unlike last week.

Instead, the jet stream will stretch west to east across the nation later this weekend through early next week. This configuration generally allows for average to slightly above average temperatures. Sunday and Monday highs generally range from the 60’s in the I-20 corridor to the 70’s along the upper Gulf Coast.

As the rain shifts in the Midwest and Northeast, travel conditions will improve significantly in the South Central region on Saturday and in the Southeast on Sunday. Any rain and fog that could cause brief travel delays to start the day Sunday from Florida to coastal Carolinas should clear by noon.