Another Flood Threat May Be Ahead for Parts of the South

Published Oct 27 2015 06:54 PM EDT

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Another Round of Rain for the South, Midwest

Meteorologist Danielle Banks talks about another round of wet weather moving through the South up into the Midwest this week and into the holiday weekend. 

Another flood threat may be brewing for parts of Texas and the South late this week, courtesy of a new storm system. The potential for flooding is higher due to last week's extreme rainfall in many of these same areas.
A southward dip in the jet stream, or trough, will move from the Southwest into the southern Plains late this week into the weekend.
As this storm system moves east, heavy rain is expected to spread from the southern Plains into the lower Mississippi Valley and portions of the Deep South.

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Heavy Rain Threat Setup Late This Week

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Estimated Rainfall Oct. 20 - Oct. 27

 

Heavy Rain and Thunderstorm Setup

The next southward dip in the jet stream digs into the Southwest late this week and moves through Texas this weekend. An area of low pressure will develop over the Southwest on Thursday and will then move across Texas and eventually the Lower Mississippi Valley.
There are indications that the storm system will be more progressive and will not move as slowly as once thought.
However, even if this system moves along relatively quickly flash flooding will remain a threat, mainly due to the amount of rainfall that fell late last week and into this past weekend, which has left the ground saturated. Consequently, there is less room for the water to be stored and it will not take as much rainfall to result in flooding.
One of the areas that was hit hardest with the last deluge was Corsicana, Texas, which saw more than 20 inches of rain late last week into the weekend. With the recent rains, Dallas-Fort Worth International Airport has now seen 46.67 inches of rain in 2015, making it the seventh wettest year on record there.
The heavy rainfall was not limited to just Texas. New Orleans received nearly 9 inches of rain Sunday into Monday, putting an end to what had been a dry October. Farther east, Mobile, Alabama, measured 5.1 inches of rainfall Sunday into Monday, and Pensacola, Florida, reported 6.74 inches of rain.
There will be plenty of moisture with this next system, but at this time it looks like there will be a smaller timeframe for the rain to accumulate than the previous system.
Widespread rainfall totals of 1 to 3 inches are expected across the southern Plains and into the Lower Mississippi Valley, with pockets of over 4 inches of rain possible.

Rainfall Forecast

In addition to the threat of heavy rain, moderate instability in the atmosphere and high dew point values will also lead to the potential for the development of a few severe thunderstorms in portions of Texas Friday. That threat will shift to the east on Saturday.

Timing of the Rain

This system will start to become organized in the Southwest Thursday into Friday. Scattered showers and storms are expected across much of the Southwest, while snow will fall across the higher elevations of Utah, Colorado, New Mexico and Arizona.
Then the rain will begin to move into Texas Thursday night and will continue pushing eastward into parts of the southern Plains, Lower Mississippi Valley and Deep South into this weekend.
Thursday night: Rain and thunderstorms will spread across much of Texas, with far eastern sections remaining dry. The heaviest rainfall is expected in western and central Texas into early Friday morning.

Thursday Night's Forecast

Friday: Rain will encompass Texas and Oklahoma and will spread into Arkansas and Louisiana later in the day and overnight. The heaviest rainfall will likely be in southern and central Texas and into south-central Oklahoma.
There is also the risk of an isolated severe thunderstorm in western Oklahoma and western Texas.

Friday's Forecast

Saturday: The rain will persist from the eastern half of Texas and central and eastern Oklahoma into Arkansas and Louisiana. Rain will also move farther east into Mississippi, Tennessee and much of Alabama. During Halloween night, the chance for rain will reach into Georgia, the Florida Panhandle and parts of North and South Carolina. The heaviest rainfall is expected in eastern Texas, southern Oklahoma, Lousiana and Arkansas.
Scattered severe thunderstorms may develop from southeastern Oklahoma and southwestern Arkansas into western Louisiana and eastern Texas.

Saturday's Forecast

Sunday: Showers and thunderstorms will continue from northeastern Texas and eastern Oklahoma eastward into Georgia and South Carolina. Locally heavy rainfall is possible from Louisiana into Mississippi, Alabama, southern Tennesee and northern Georgia.
The threat of severe thunderstorms will also be a concern in eastern Texas and the lower and middle Mississippi Valley.
The chance for heavy rain decreases to start next week, but showers will continue for parts of the South and East.
MORE ON WEATHER.COM: October 2015 Flooding in the South (PHOTOS)

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