Catastrophic flooding in North Carolina was caused by mountainous terrain and heavy rainfall

Extreme Weather Events in North Carolina was caused by mountainous terrain and heavy rainfall Hurricane Helene was predicted by meteorologists to become a “once-in-a-generation” hurricane for parts of the Appalachians, and over mountainous areas of Georgia, South Carolina, eastern Tennessee, and western North Carolina, the prediction proved to be tragically correct.

Corey Davis, North Carolina assistant state climatologist, wrote in a blog post on Monday that “the most severe flooding ever observed” occurred in western North Carolina as a result of the region’s unique geography and the copious quantities of rain that fell before and during Hurricane Helene.

An unlucky confluence of topography, hydrology, and weather led to the devastating flood calamity, experts told USA TODAY on Monday.

Rainfall that was almost unimaginably heavy dropped over a 200-mile stretch over the United States, collapsing mountain streams into unidentifiable rivers and gushing from towering summits. In Western North Carolina, entire communities were shut off by rushing torrents that swamped valleys, totally encircling an East Tennessee hospital.

Rain before the tempest

Rainfall from Helene would have been sufficient to cause flooding anywhere, but David Easterling, a rain expert with the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information in Asheville, North Carolina, said it was made worse by a weather front that had stalled over the Appalachians before the arrival of then-Tropical Storm Helene.

However, by that time, rain was falling in the mountains due to a line of slow-moving showers that had formed from Atlanta across the southern Appalachians following a stalled cold front. The cold front was being fed by tropical moisture from Helene’s southern outskirts.

Mountains intensified the rainfall.

According to Easterling, in certain locations, the mountains themselves increase the rainfall since they are a part of the lift that causes thunderstorms to create extra rain.

“There was rain for at least thirty hours,” he stated. And over 25 inches fell in some areas.

He said, “All that rain gets channeled into smaller streams to flow into bigger streams when it comes down.” He added that those streams were gushing water in the direction of the larger rivers.

Unfavorable landscape

The topography not only made the rains heavier, but it also caused massive flooding.

“There are steep slopes and shallow soil, so the terrain is not conducive to intense rainfall,” National Water Center’s Russ Barton of NOAA told USA TODAY. According to him, the majority of the infrastructure is located in the valleys, where all of the floodwaters go.

Easterling, a resident of the area and one of the thousands without power claimed that all of that water was flowing into these bigger rivers and inundating everything that was near a river.

According to him, mudslides and landslides were bringing down poles all over the place, and strong gusts were bringing down trees and electricity lines.

Conclusion

A perfect storm fuelled by the force of nature and unfavorable topography can have fatal consequences, as demonstrated by the terrible flooding that has devastated North Carolina and the neighboring counties.