In late summer, a relatively weak tropical system has left a staggering mark on the U.S. Gulf Coast, with preliminary assessments from AccuWeather forecasting total damage and economic losses ranging between $4 billion and $6 billion. Tropical Storm Arthur, which spent less than 24 hours officially classified at tropical storm strength after forming off the Texas coast, unleashed catastrophic, life-threatening weather across a multi-state stretch from Texas to the Florida Panhandle, with Louisiana and Mississippi bearing the brunt of the destruction.
Record-shattering rainfall amounts overwhelmed local infrastructure across the region. In Cottonport, Louisiana, the storm dumped a total of 31.56 inches of rain over just a few days, while nearby Plaucheville and Simmesport recorded 24.47 inches and 20.66 inches respectively. Even in Carriere, Mississippi, totals reached 15.75 inches, far exceeding the capacity of local drainage systems. The extreme precipitation sparked widespread flash flooding that closed dozens of roads, inundated hundreds of homes and businesses, and forced emergency teams to carry out dozens of high-water rescues. As of 7 a.m. Friday, at least two fatalities have been confirmed, two tornadoes have been recorded in Louisiana, and additional twisters are expected to be documented as assessment teams reach isolated areas.
AccuWeather’s preliminary estimate accounts for every dimension of the storm’s economic footprint, from direct physical damage to homes, businesses and public infrastructure to indirect costs including extended business interruptions, hundreds of flight delays, prolonged power outages, supply chain disruptions, crop losses, emergency evacuation and response expenses, and ongoing recovery costs. AccuWeather experts note the final total could climb even higher, as many hard-hit areas have not yet submitted full damage reports, and lingering impacts continue to disrupt local communities weeks after floodwaters first rose.
“Flooding, travel disruptions, power outages and business interruptions can quickly add up to billions of dollars in impacts for families, businesses and communities,” said Dan DePodwin, AccuWeather Vice President of Forecasting Operations. “Arthur is another reminder that tropical systems do not need to reach hurricane strength to cause significant, expensive and even deadly damage and economic losses.”
Flooding was by far the costliest impact of the storm, a pattern DePodwin says is common for weaker tropical systems that move inland. To better communicate the full scope of a storm’s threat beyond just wind speed, AccuWeather used its proprietary RealImpact™ Scale for Hurricanes to rate Arthur a 2, due to its life-threatening flooding. This differs from the traditional Saffir-Simpson scale, which only ranks storms by wind speed and would have classified Arthur as a low-level event before dissipation.
“Arthur is a clear example of why the AccuWeather RealImpact Scale for Hurricanes is so important. Instead of classifying a storm’s threat by just its wind speed, the scale accounts for the other many threats that are caused by tropical systems. Storm surge, and in the case of Arthur flooding, are typically responsible for more widespread impacts than wind damage alone and more people are killed by water than wind in tropical systems. Some of the most destructive flood events in our nation’s history were caused by tropical storms or unnamed tropical rainstorms,” DePodwin added.
AccuWeather’s damage estimate uses independent, proprietary methodology that incorporates both insured and uninsured losses, drawing on a wide range of public and proprietary data sources to capture both short-term and long-term economic impacts. The company has been a leading provider of preliminary disaster damage estimates since 2017, when its widely cited early assessment of Hurricane Harvey helped the public and policymakers grasp the full scale of that catastrophic event. Unlike many partial assessments that only count insured property damage, AccuWeather’s methodology includes lost wages and business income, cleanup and emergency management costs, long-term disruptions to tourism and transportation, and even unreported medical and mortality costs that are often omitted from official early estimates.