In the wake of Tropical Storm Arthur, Louisiana parishes are facing severe flooding challenges. The storm’s unprecedented rainfall has broken records and is causing widespread disruption, while a new report from Moody’s highlights the nation’s growing vulnerability to uninsured flood losses.
The situation in Louisiana is critical, with floodwaters moving from Avoyelles Parish into St. Landry Parish and threatening to impact even more communities in the coming days.
Record-breaking rainfall and flooding in Louisiana
Parts of Avoyelles Parish have experienced historic flooding following Tropical Storm Arthur. One resident in Cottonport measured nearly 30 inches of rainfall in less than 12 hours, a staggering amount that has overwhelmed local infrastructure.
Jonathan Brazzell, a hydrologist with the National Weather Service described the rainfall as a 1,000-year flood event with only a 0.1% chance of occurring in any given year. If verified, this rainfall would break the state’s previous 24-hour record of 22 inches set in Hackberry.
The storm’s impact is not confined to Avoyelles Parish. Doug Kramer, a meteorologist with the National Weather Service, reported that floodwaters are moving into St. Landry Parish, causing property damagecrop losses and road closures. The water is expected to continue moving into St. Martin Parish and eventually into the Atchafalaya Basin.
The nation’s growing flood insurance protection gap
A new whitepaper from Moody’s reveals that the U.S. faces a widening gap between growing flood risk and the take-up of flood insurance. The report estimates that the nation could face more than $375 billion in aggregated uninsured flood losses from a 1-in-100-year event.
The insurance protection gap, now at 65%, poses a significant financial risk to households and local governments. Many rely on FEMA’s Specific Flood Hazard Area (SFHA) maps, which primarily account for riverine flooding and often fail to consider flood risk from storm surge, sea level rise, or extreme precipitation.
Moody’s analysis used the Moody’s RMS US Inland Flood HD model to assess residential flood risk in the U.S. The report found that in a 1-in-100-year flood scenario, less than 2% of counties in 11 states carry 65% of the country’s uninsured loss exposure. Counties in Florida, Louisiana, South Carolina, and Texas face more than $5 billion in potential uninsured losses.
The limitations of current flood risk assessment
The report highlights the limitations of relying solely on backward-looking statistics to characterize flood risk. As climate change alters precipitation patterns, the frequency and severity of flood events are expected to increase, outpacing current insurance coverage.
For instance, Asheville, North Carolina, experienced rainfall far above the expected amount from a 1-in-1,000-year event during Hurricane Helene in September 2026. Buncombe County, home to Asheville, had a flood insurance protection gap of 88%, illustrating the growing disparity between flood risk and insurance coverage.
Moody’s projects that uninsured loss exposure from a 1-in-100-year flood event could increase nationwide by about 25% on average by 2050, reaching around $472 billion. This underscores the urgent need for updated flood risk assessment methods and increased insurance coverage to protect communities from the growing threat of flooding.