(Reuters) - The downpour that inundated parts of Colorado this month was a once-in-a-millennium event for those areas, according to an analysis by the National Weather Service.
Colorado residents are coping with widespread destruction from floods unleashed by torrential rains that began on September 9 and lasted for several days. The flooding killed at least eight people, forced thousands from their homes and caused nearly $2 billion in property damage.
Towns at the base of Colorado's so-called Front Range in Larimer and Boulder counties, northwest of Denver, experienced the most damage.
"As it kept raining and kept raining and kept raining, this thing kept getting more and more rare, in terms that we use for evaluating," said Geoffrey Bonnin, chief of the Hydrologic Science and Modeling Branch of the National Weather Service.
To date, monthly rainfall for September in Boulder, Colorado, totaled 17.2 inches, the most for any month since official recordkeeping began in 1893, said Byron Louis, program manager for the National Weather Service in Colorado.
Rain in that area fell nearly continuously from September 9 to September 15, Louis said.
That amount of rainfall around Boulder is likely to occur less than once every 1,000 years, according to the weather service.
