ONE Expected hurricane season activity North Carolina first hit last week, with four days of rain from slow-moving Tropical Storm Debby inundating much of the state.
That heavy rain had fallen on the ground and the streams were saturated after a July wettest on record for some areas of eastern North Carolina, which creates flooding problems as our major rivers reach major flood stages.
And Debby’s damage didn’t stop with flooding. Tornadoes in its outer bands also left their mark on towns across eastern North Carolina, adding to the impact of a tropical storm well beyond its strength.
A slow arrival
Debby’s Path to North Carolina began on the last day of July, when a tropical disturbance moved across warm water in the northern Caribbean Sea. After passing through the rugged terrain of Puerto Rico, Hispaniola, and Cuba, Debby became a tropical storm on Saturday, August 3.
During its short trip north toward the Gulf Coast, Debby reached Category 1 hurricane strength. However, in a harbinger for our state, the worst damage in Florida was not caused by winds near the eye of the storm, but by Flooding along the Florida coastincluding in Sarasota later over 17 inches of rain fall locally
The storm then moved across the Atlantic coast, continuing northward on its way to landfall in South Carolina, similar to Hurricane Ian in 2022.
But Debby also slows down considerably, because it really boxed in by high pressure to the east and west and a stalled front to the north. When it reappeared off the coast of Georgia last Tuesday, Debby had a forward speed of just 3 miles per hour – a return to a slow pace Florence took place across the Carolinas six years ago.
As the outer bands stretched ahead of the storm, rain spread across North Carolina starting Tuesday morning. In the first 24 hours, the south coast saw the heaviest rainfall, including 5.66 inches. Wilmington – highest daily total since Hurricane Dorian in 2019.
Via early thursday morning As the storm neared landfall just north of Charleston, S.C., its rain began spreading west across the Piedmont. Rainfall totals in that area on Thursday neared or exceeded four inches, including 3.91 inches Greensboro4.02 inches in Raleighand 4.24 inches in Charlotte.
The center of Tropical Depression Debby moved north of us early Friday morning, but rain continued throughout the day across the eastern half of the state. Further west, multiple showers associated with a passing cold front dropped another 2 to 5 inches of rain across parts of the Piedmont, resulting in Flooding and multiple water rescues in Guilford County.
Heavy rain and other hazards
In four days of rain, Debby dumped more than six inches of rain on southeastern North Carolina, with some areas getting more than ten inches of rain, such as 10.70 inches in Wilmington. Among our ECONet, 13 of the 45 stations recorded at least 5 inches of raincovers 9.12 inches in Hayne Castle and 8.91 inches in Whiteville.
That rain added to what we got in July to continue the recent wet weather pattern, especially in eastern North Carolina. With 4.46 inches of rain from Debby as of August 9, Greenville had 19.40 inches of rain in the previous 30 days – more than a third of the average annual rainfall fell in just one month.
The heaviest rainfall from Debby occurred in northern Brunswick County. A citizen weather watcher in Leland had one total number of storms of 15.75 inches, while a pair of nearby CoCoRaHS observers recorded over 14 inches. Elsewhere in the county, Shallots reached 10.34 inches, the fourth highest rainfall in a single four-day period since the station began keeping records in 2000.
Tree roots are weakened in rain-soaked soil, coupled with strong winds – with strongest gust of 52 miles per hour at both Fayetteville And Greensboro – created a recipe for falling trees and power outages. The governor’s office recorded a total of nearly 480,000 power outages statewide
Although Debby was a low-level tropical storm with maximum sustained winds of just 50 mph when it made landfall on the South Carolina coast Thursday morning, its destructive power was still immense in its outer bands.
The National Weather Service has confirmed 10 tornadoes in North Carolina during Hurricane Debby, which is the largest tornado outbreak in the state from a tropical system since 11 from Hurricane Isaiah in 2020.
Three tornadoes landed in Franklin County, along with a couple from Pender County (with a person who then moved to Sampson County) and one for each person Brunswick, Edgecombe, Green, NashAnd Wilson counties. Tornado in Wilson County, Springfield High School damaged in the town of Lucama, achieve EF3 power with winds of 140 mph.
It was an unusually strong tornado for a tropical storm. In fact, it was only the third F3 or EF3 tornado recorded in North Carolina associated with a tropical system. Isaias produced an EF3 tornado in Bertie County, and Hurricane Cleo in 1964 produced an F3 tornado in Scotland County.
Three deaths in North Carolina have been blamed on Debby. A tornado in Lucama caused a house to collapse, kill the man inside. In Rockingham County, a the woman was killed when a tree fell on her home. And in Robeson County, a dead woman after her car was swept away by floodwaters.
Rising rivers and familiar floods
The timing of Debby’s forecast right after our wet July means there is little room in the soil or streams to store excess moisture, so water has run off into the rivers and caused some high flood peaks since the storm passed.
Water levels on three of our major rivers reached major flood stage over the weekend. Lumber River in Lumberton peaked nearly two feet above peak flood levels, while Tar River in Louisburg overcome the flood stage for the first time since Hurricane Matthew in 2016.
In Cumberland County, which has seen total local more than eight inches, Little River in Manchester reaching the sixth highest peak on record at 27.71 feet, behind only the peaks associated with Florence, Matthew, and Storm of September 1945.
Elsewhere in the county, Some parts of Interstate 95 have been closed. due to flooding on the road, and a the dam has broken in Fayetteville due to fast-flowing water. Another dam failure was reported in Harnett County when an earthen dam surrounding a pond broke, promote local evacuation.
On Monday, another river gauge reached major flood stage. Northeast Cape Fear River near Burgaw at 16.13 feet and still rising, with a crest expected Tuesday morning — exactly seven days after rain from Debby began falling. Other locations across far eastern North Carolina could also crest early this week as water continues to flow downstream.
While the flooding in Debby was fortunately not as widespread as after Hurricanes Matthew or Florence, many of the same areas were still affected, making this the third major flood in eight years.
That thing frequency and intensity increased of extreme rainfall events from tropical systems is consistent with what we expect in a warming climate. Slow-moving storms like Debby are also becoming more common as global tropical circulations weaken due to climate change. One study noted that 16% speed reduction for hurricanes affecting land areas in the North Atlantic from 1949 to 2016. Combined with a warmer, wetter atmosphere, this has increased total rainfall about 25%.
It’s also our latest reminder that maximum wind speeds or minimum pressures rarely fully reflect the nature of a storm, especially in a long-running event defined more by impacts far from the storm’s center like heavy rains and deadly tornadoes.
Debby’s ultimate legacy may be shaped by how the rest of this hurricane season plays out, and whether it’s a one-off storm or the first of many to impact us this year.
For now, we consider this a tropical storm with the attitude (and impact) of a hurricane, and a reminder of other recent storms that have left their mark, from Ian’s northward path through South Carolina to Florence’s sluggish pace to the flooded roads and dam failures in Fayetteville reminiscent of Matthew.
