# Unmatched Flooding from Hurricane Helene: A Landmark Incident in Western North Carolina
*Hurricane Helene carried moisture from both the Gulf and Atlantic into the southeastern United States.*
*Image credit: NOAA*
As of Monday morning, the aftermath of **Hurricane Helene** has left an alarming imprint on western North Carolina and nearby regions. To appreciate the extraordinary character of the flooding, one could reference the **National Climatic Data Center (NCDC)**. This national agency, which maintains the largest climate data collection in the world, offers historical insight into weather patterns and natural calamities, especially in an era increasingly influenced by climate change.
However, the NCDC, situated in **Asheville, North Carolina**, is presently offline. The city, nestled within the Blue Ridge Mountains, has emerged as the focal point of devastating flooding triggered by Helene. The climate data facility is non-functional as water and electricity services have faced considerable disruption due to the historic flooding.
During a press conference over the weekend, **North Carolina Governor Roy Cooper** characterized the flooding as an “unprecedented” disaster. Nearly 500,000 residents are left without power, and many are deprived of access to clean drinking water. The official death toll has reached at least thirty-six, while viral videos depict catastrophic scenes of devastation, including dam collapses and inundated highways.
## What Caused Such Destruction So Far from the Coast?
One of the most puzzling elements of this catastrophe is how an area almost 500 miles from the Gulf of Mexico could suffer such extensive damage from a hurricane that originated there. The explanation lies in the unusual behavior of **Hurricane Helene**.
Helene made landfall in the Gulf of Mexico as one of the quickest-moving storms in recent memory. Its swift advance inland formed a substantial river of atmospheric moisture, directed into regions of **North Carolina**, **northern Georgia**, and **southeastern Tennessee**. This phenomenon, known as **atmospheric rivers**, can convey immense quantities of water vapor over considerable distances, resulting in significant rainfall far from the storm’s source.
Although the precise volume of moisture carried by Helene is still under investigation, initial assessments indicate that the event was historic. According to **meteorologist Ben Noll**, the moisture level transported into western North Carolina was more than **1.5 times higher** than any previous occurrence recorded for the region.
By utilizing a measure known as **integrated vapor transport (IVT)**, which factors in specific humidity, wind elements, and pressure changes, Noll estimates that around **3,000 kilograms of water vapor per meter per second** were directed into North Carolina at the storm’s peak. This eclipsed the previous benchmark of **1,883 kilograms**. While Noll’s findings are preliminary and await peer review, they offer insight into the extraordinary nature of this event.
*Helene seems to have established records for moisture directed into North Carolina.*
*Image credit: Ben Noll*
## Intense Rainfall and Severe Flooding
The excessive moisture carried by Helene led to **record-setting rainfall** throughout various parts of North Carolina. Some isolated locations witnessed more than **30 inches (76 cm)** of rain, while widespread totals of **15 inches or more** were documented. Though such rainfall figures are not unusual along the Gulf Coast during especially powerful tropical storms and hurricanes, they are remarkable for areas located so far inland.
The undulating landscape of the **Appalachian Mountains** is poorly equipped to deal with such immense rainfall. Consequently, multiple dams have breached, residences have been obliterated, and vital infrastructure has suffered significant harm. The **National Weather Service (NWS)** declared more flash flood emergencies during this storm than any other in its history, highlighting the seriousness of the situation.
## An Uncommon but Not Unprecedented Phenomenon
While the flooding caused by Hurricane Helene is historic, it is not entirely without precedent. A similar event took place in **1969** with **Hurricane Camille**. After making landfall in southeastern Louisiana, Camille traversed across Mississippi, Tennessee, Kentucky, and West Virginia before interacting with a frontal boundary over Virginia. This interaction generated immense rainfall totals of up to **25 inches** in certain locales.
In **Nelson County, Virginia**, a rural area situated west of Richmond, flooding from Camille destroyed **133 bridges** and resulted in approximately **153 fatalities**. The destruction wrought by Camille serves as a reminder that hurricanes can have extensive repercussions, even in areas significantly distant from the coastline.
## The Influence of Climate Change
