A lone tree stands amid a torrent of water as it rushes down Cherry Creek and covers the adjoining bicycle path as heavy rains fall across the metropolitan area Thursday, May 11, 2023, in Denver. (AP Photo/David Zalubowski)

Executive Summary

Following catastrophic flooding along Elevenmile Creek in Cantonment, Florida, near Pensacola, AccuWeather’s Forensic Services team investigated the extreme rainfall of April 29–30, 2014, to determine the role weather played in the flooding.

AccuWeather’s forensic meteorological analysis determined that nearly 24 inches of rain fell along portions of the creek, making it the heaviest rainstorm on record for the area and exceeding rainfall associated with hurricanes that had affected that part of Florida. The analysis concluded that rainfall of this magnitude was sufficient to produce catastrophic flooding along Elevenmile Creek regardless of the presence of a relatively small retention pond on an upstream property.

Key Takeaways

-- AccuWeather investigated the April 29–30, 2014 rainfall and flooding along Elevenmile Creek near Pensacola, Florida.

-- The forensic analysis determined that nearly 24 inches of rain fell along portions of the creek.

-- AccuWeather determined that it was the heaviest rainstorm on record for the area, exceeding rainfall from hurricanes that had previously affected that part of Florida.

-- The analysis concluded that the extreme rainfall was sufficient to cause catastrophic creek flooding regardless of the presence of the upstream retention pond.

-- AccuWeather meteorologist Steve Wistar provided expert meteorological testimony at trial about the severity and historical significance of the storm.

What caused the flooding along Elevenmile Creek?

A major flood affected numerous homes along Elevenmile Creek in Cantonment, Florida, following extreme rainfall on April 29–30, 2014. Homeowners subsequently brought litigation involving an upstream International Paper property, alleging that overflow from a containment pond contributed to the severity of the flooding.

AccuWeather’s expert forensic meteorologists were retained to investigate the rainfall and determine the meteorological conditions that contributed to the flood.

What did AccuWeather meteorologists find?

AccuWeather reconstructed rainfall conditions along Elevenmile Creek and the surrounding area. The analysis determined that nearly 24 inches of rain fell along portions of the creek during the event.

AccuWeather concluded that the storm represented the heaviest rainfall event on record for the area and produced more rain than hurricanes that had previously affected that part of Florida.

The magnitude of the rainfall was critical to understanding the resulting flooding. AccuWeather’s analysis concluded that an event of this severity was capable of producing catastrophic flooding along Elevenmile Creek independent of the relatively small retention pond located on the International Paper property.

A hydrologist involved in the case for the same clients separately testified that only a small percentage of the water flowing down the creek would have originated from the International Paper property.

How did forensic weather analysis support the litigation?

AccuWeather meteorologist Steve Wistar testified at trial, providing expert analysis of the storm’s rainfall intensity and historical significance.

The case illustrates an important role of forensic meteorology in flood litigation: Determining not simply whether heavy rain occurred, but how much rain fell at the relevant location, how unusual the event was compared with the historical record, and whether the meteorological conditions were sufficient to explain the resulting damage.

By reconstructing extreme weather events using historical weather data and expert analysis, forensic meteorologists can provide attorneys, insurers, engineers, and other stakeholders with scientifically supported evidence about the role weather played in flooding and property damage.

Slow-moving nor'easter to spread gusty winds to Northeast coast