Forecasters are predicting flooding could match what Halifax County residents saw in Riverdale in October of 2018 when remnants of Hurricane Michael ravished the area.

In a Thursday afternoon update, the National Weather Service issued a statement saying the forecast had increased from minor to moderate severity with the Dan River now predicting to crest at 31.4 feet Saturday evening, with it falling below flood stage Monday morning.

With this latest forecast, flooding could close the intersection of Routes 501 and 58, according to the National Weather Service.

Motorists who typically travel U.S. 501 and U.S. 58 in the Riverdale area should plan to take a detour through an alternate route Friday and potentially Saturday, as well.

“It is anticipated that 501 will be closed tomorrow (Friday) about noon,” said Steve Dishman, emergency services coordinator for Halifax County, on Thursday, and he will be monitoring the area to see when it reaches Route 58.

Dishman explained that once the river meets the 30 feet mark then it can reach Route 58.

Originally forecasters with the National Weather Service said the river should crest Saturday at 28.8 feet, but later upped the forecast as rainfall pounded the area.

This will be the third time this year that the Riverdale area of South Boston has flooded.

On Feb. 9, the Dan River at South Boston crested at about 30.6 feet, flooding Riverdale businesses. Once again on May 24, the Dan River flooded, topping out at 30.1 feet, forcing Riverdale merchants to move their merchandise to higher ground.

In addition to swelling the waters of the Dan River, Thursday’s heavy rains also were predicted to cause flash flooding of low-lying areas.

“The National Weather Service has a campaign: ‘Turn around, don’t drown,’” Dishman said. “Don’t drive through water flooding over the roadway, because you don’t know the road conditions under that. The road could be washed out.”

As of Thursday morning, Sleighter said between one and one and a half inches of rain had fallen in the southeast part of Halifax County, with higher rainfall amounts in the three to four-inch range in the western and northern parts of the county.

An additional half-inch to three-quarters of an inch of rain was expected to fall Thursday.

While the Dan River at South Boston will crest just below moderate flood stage, the Roanoke (Staunton) River at Brookneal was forecast to reach major flood stage, peaking at 33.4 feet Thursday evening and falling below flood stage by Saturday morning, according to the National Weather Service.

Further downstream at Randolph, the Roanoke River is forecast to reach minor flood stage and peak at 29.8 feet early Friday afternoon. At 25 feet, water is several feet deep on portions of River Road and Black Walnut Road, and at 30 feet, water begins to reach the base of the Randolph Post Office, according to the National Weather Service.

The Dan River at Paces also was forecast to reach minor flood stage, and a flood warning remains in effect until Sunday morning.

Minor flood stage for that area of the river is 22 feet, and the National Weather Service forecasts the river to continue rising throughout the day Friday before peaking Friday evening at 28 feet.

At 24 feet, low spots along Routes 658 and 671 begin to flood. At 29 feet, water reaches the underside of the Route 658 bridge over the Dan River.

While the rainfall amounts in the South Boston area from Wednesday and Thursday’s weather system are not significant, much higher rainfall amounts fell further to the west, just east of the Blue Ridge Mountains, flowing downstream along the Dan River to South Boston and resulting in the river flooding.

“Whatever water falls into the Dan River from the Patrick County/ Stuart area down through Madison/ Mayodan/ Eden, North Carolina comes down here to South Boston and affects us,” Dishman explained.

At the same time, Dishman noted any rain that falls in the Roanoke area and south of Roanoke flows into the Staunton River, also making its way to Halifax County.

Miranda Baines is a staff writer for The Gazette-Virginian. Contact her at mbaines@gazettevirginian.com.

Miranda Baines is a staff writer for The Gazette-Virginian. Contact her at mbaines@gazettevirginian.com.