For the second time in just six weeks, some areas of southeastern North Carolina saw more than a foot of rain from a slow-moving storm system.
The latest event has exceeded the total and impact of local flooding from Tropical Storm Debby in August, and perhaps most impressively, it wasn’t even a classified tropical storm or hurricane.
The first offshore system was developed last Saturday along the The front boundary is stagnant.. While the National Hurricane Center has given it a preliminary investigation as to Potential Tropical Storm No. 8They never found a clearly defined circulation center – a crucial part of structure of tropical cyclone – And they have noted Any low-level circulation extending from northeast to southwest is a remnant of its frontal origin.
Although classified as a regular low pressure system, its impact on North Carolina is anything but ordinary. It sits atop the Atlantic’s rich moisture reservoirs and drifts at a very slow pace. 3 miles per hour By Monday morning, it had actually turned its fire hose on our state for four straight days.
If those details sound familiar, it’s because there are a lot of similarities to Debby, from the same forward crawling speed to the same duration – delayed again by the barrier of high pressure north and west – following a nearly identical path moving northwest through the Carolinas. That means many of the same areas were affected during and after Hurricane Debby.
Heavy rain and flooding
Storm-related rainfall totals of at least 2 inches were recorded as far west as Haywood County, with widespread coverage of higher rainfall amounts across central and eastern North Carolina. Some areas in the northwestern Piedmont received heavier rainfall from storm band on Tuesday night, including 6.87 inches at our ECONet station in Reidsville.
The highest rainfall totals exceeding eight inches occurred in the Southern Coastal Plain, with more than 12 inches in New Hanover and Brunswick counties. storm summaryThe National Weather Service in Wilmington recorded a storm total of 20.81 inches of rain on Ocean Boulevard on Carolina Beachand several CoCoRaHS observers in southern Brunswick County measured over 15 inchesincluding a maximum of 20.19 inches near South Port.
Our office’s ECONet station on Bald Island reported 20.26 inches from Saturday to Monday, including 12.29 inches on Monday alone, which was the wettest day our stations on the island have measured since 2015. Along with the rain, Bald Head Island also had short-lived tornado on Sunday morning after the tornado moved ashore.
Remote Automated Weather Station (RAWS) at Sunny Point Military Station Total rainfall was 18.79 inches, with the largest one-hour rainfall of 4.61 inches reported at 11:18 a.m. Monday.
After that rain, the Lumber, Neuse and lower Cape Fear rivers all rose to flood stage, with the Northeast Cape Fear River near Burgaw expected to peak at or near moderate flood level.
For coastal communities, the impact is much more immediate. Many roads, including state highways in Brunswick County, have been flood or wash clean. The town of Carolina Beach is flooded at least three feet deep. And local elementary school students were evacuated by amphibious vehicles amid rapidly rising floodwaters on Monday.
Another extreme event
For an event that began six years after that day Hurricane Florence Landfall, PTC8 is another reminder that Florence is not the only flooding storm in our state’s recent history.
It was involved in Tropical Storm Idalia. Flooding in Whiteville and the swollen rivers and flooded roads following Hurricane Debby were among the most devastating flooding events in just the past 13 months.
This latest storm adds to evidence that these extreme rainfall events are more common than ever. That’s evident in the data itself. Frequency of return rain from the older Atlas-14 dataset considers 20.26 inches of rainfall over three days on Bald Head Island to be a roughly 1 in 500 year event.
Southport had a similar event at 1/500 in Hurricane Floyd in 1999, with 18.30 inches in just 24 hours. And southern New Hanover County had 31.26 inches in four days during Hurricane Florence: far surpassing the 1,000-year rainfall total of 24.2 inches from the historical Atlas-14 dataset.
Along with demonstrating the need for more accurate and up-to-date rainfall frequency data – and our office is currently undertaking such a project to provide our partners like the North Carolina Department of Transportation with a better view of these extreme events – the recent series of storms and floods continues to highlight the dramatic impacts of climate change in North Carolina.
A warmer, wetter atmosphere means storm events – including the storms – is getting too humid, and our rarest wet days are become much more popular. Recent trends also shows that storms are moving more slowly closer to land and high pressure patterns are being blocked become more popularThis increases the chance of rain when those systems combine.
For some of our southern coast, that potential was realized again this week, when 20 inches of rain left behind familiar flooding scenes and helped this unnamed storm earn a reputation as one of the wettest local storms on record.
