Sep 17, 2013

Historic Rainfall and Floods in Colorado

1604 Arapahoe Ave, Boulder, CO
USA
by
Michon Scott
,
NOAA
Grounds of Boulder High School on September 13, following historic rainfall and flooding. By September 16, the month-to-date precipitation was already more than 1.7 times any monthly rainfall total since records began in the late 1880s. Photo: Bruce H. Raup
Grounds of Boulder High School on September 13, following historic rainfall and flooding. By September 16, the month-to-date precipitation was already more than 1.7 times any monthly rainfall total since records began in the late 1880s. Photo: Bruce H. Raup

Flood conditions stretched about 150 miles, from Colorado Springs north to Ft. Collins. Saturated soils left water with no place to go, and puddles turned to ponds throughout the densely populated Colorado Front Range. Rainwater swelled rivers and creeks, overtopped dams, flooded basements, and washed out roads. By September 16, authorities had confirmed six deaths, and more than 1,000 people remained missing...

Boulder's 2013 flood not only brought unusual rainfall, it came at an unusual time. On average, April and May are Boulder's wettest months, with precipitation totals of 2.45 and 3.04 inches, respectively, between 1948 and 2005, according to the Desert Research Institute...

As for whether a warming climate played a part in this historic storm, Bob Henson of the University Corporation for Atmospheric Research described the event as an "excellent candidate for an attribution and detection study." Computerized climate models enable scientists to test how frequently similar storms might occur with or without fossil fuel use