Flash Flood Threat in Deep South, Gulf Coast, Carolinas Through Tuesday

Jon Erdman
Published: November 7,2015

Additional heavy rain and flash flooding will target parts of the South, Gulf Coast, and Southeast Coast through Tuesday, including rain-weary parts of the Carolinas, Texas and Louisiana.
Over the past few weeks, torrential rain has triggered destructive flash flooding in parts of Texas and Louisiana, in particular. Parts of South Carolina were also swamped by a double-whammy of historically heavy rain and coastal flooding in early October.
(MORE: One of South's Wettest Years, So Far)

The setup for soaking rain in the South, Gulf Coast and Carolinas into Monday and Tuesday.

Current Radar, Watches and Warnings

Sunday's Forecast

Monday's Forecast

Rainfall Forecast Through Tuesday

While likely not nearly as prolific as any of those past events, a number of factors are combining to raise yet another flood threat in this region.
































































First, a cold front is sagging slowly into the South, but will stall out over the eastern Gulf of Mexico and near the Southeast coast.
A strong subtropical jet stream will ride along that frontal boundary, inducing weak waves of surface low pressure along the front from the northern Gulf Coast to just off the coast of the Carolinas the next few days.
A deep fetch of moisture from the Bay of Campeche, western Caribbean Sea, and far eastern Pacific Ocean is expected to feed into the Gulf Coast and Southeast coast. A second plume of moisture from a tropical disturbance that will eventually track east of the Bahamas may also have some contribution to the Carolinas rain, but nothing like what we saw in early October.
(MORE: Atlantic Tropical Development Possible)

Forecast Timing, Amounts

There has already been some local flash flooding early Saturday.
A stationary band of heavy rain produced rainfall rates over 3 inches per hour near Beaumont, Texas, leading to street flooding in the city of Central Gardens.
(INTERACTIVE: National Radar Map)

Saturday Night

• Rain will persist from Louisiana to the Carolinas, before the cold front finally pushes the rain threat toward the Gulf Coast overnight.
• Heaviest rain, local flash flooding: Southeastern Louisiana to southern Mississippi and southern Alabama.

Sunday

• Rain in the Southeast from Georgia, Alabama and South Carolina to north and central Florida, including the Florida panhandle.
• Heaviest rain, local flash flooding: Florida Gulf Coast mainly north of Tampa, Florida panhandle.
• Drying out: Texas, Louisiana, Mississippi

Monday

• Rain continues in north, central Florida, Georgia, becomes heavier in parts of South Carolina, North Carolina, possibly persisting into early Tuesday.
• Heaviest rain, local flash flooding: north Florida, coastal Georgia, eastern South Carolina, eastern North Carolina

We expect the heavy rain threat to clear the Carolinas by later Tuesday.
(CITIES: Destin | Jacksonville | Charleston | Columbia)

Greatest Flash Flood Threat

• Parts of coastal Louisiana, the Florida panhandle, east Georgia, South Carolina and eastern North Carolina have the best chance of picking up over 2 inches of rain Sunday-early Tuesday.
• The latest NWS flash flood guidance suggests rain rates of 3-4 inches in 3 hours would trigger flash flooding from east Texas to the eastern Carolinas. 
• Rainfall rates in excess of 1 inch per hour area possible in some of these clusters of rain, that may stall out for a period of 1-3 hours, or more, at times.

(INTERACTIVE: Latest NWS Flood Alerts)
As always, respect the power of flash flooding.
Your vehicle can be the biggest danger in a flash flood. Never drive through flood waters of unknown depth and never drive around barricades blocking flooded roads. Turn around, don't drown.

PHOTOS: Tornadoes, Flooding in the South (Late Oct. 2015)