Three people are dead and hundreds have been evacuated after torrential rains have deluged the Colorado Front Range.
Widespread rainfall totals of 5-7 inches in 24 hours have fallen in the region, causing streams to swell while generating rockslides and mudslides.
In Boulder, a Flash Flood Emergency was hoisted overnight and the campus of the University of Colorado is shut down. Four hundred students were forced to evacuate, the Associated Press reports.
“This is almost certainly the heaviest 24-hour rain in Boulder history,” says Bob Henson of the National Center for Atmospheric Research, in Boulder, which is also closed today due to the flooding.
The cooperative observing station in Boulder logged 6.42 inches of rain since last night. Boulder has received almost 10 inches of rain this month, the most on record for September.
“September 2013 appears also to be the wettest month in Boulder weather history, surpassing 9.59″ in May 1995,” says John Brown, one of the observing station managers, and a scientist at NOAA.
Video of Boulder Creek flooding
The Associated Press says Boulder Police received multiple reports of flooded basements, homes, and streets, as well as submerged cars. Numerous roads are closed.
@Brandash via instagram
Of the three fatalities, two occurred in Boulder County: one from a collapsed structure in Jamestown while a second body was discovered this morning in Boulder, the Daily Camera says. The third fatality occurred from flash flooding near Colorado Springs.
— Hema Mullur (@HemaMullur) September 12, 2013
The National Weather Service says the convergence of moist flow from the southwest and southeast along the Front Range is behind the historic flood event.
“THIS FLASH FLOOD EVENT WAS FORCED BY LOW LEVEL UPSLOPE BENEATH UPPER LEVEL DIFFLUENCE…IN AN ENVIRONMENT THAT FAVORS VERY EFFICIENT RAINFALL AND LITTLE CELL MOVEMENT,” explains the NWS Weather Prediction Center.
These same circumstances may repeat this afternoon.
“[THEY] WILL PROBABLY SET THE STAGE FOR ANOTHER ROUND OF MODERATE TO HEAVY WARM PROCESS RAINFALL OVER AND ALONG THE COLORADO FRONT RANGE THIS AFTERNOON AND EVENING,” says the NWS forecast office in Boulder, Co.
Boulder is known as a location very vulnerable to extreme flooding. As the Daily Camera explains:
Boulder has long ranked as one of the state’s top flood hazards and made a national list of six “disasters waiting to happen” published by CU in 2004, along with a devastating hurricane striking New Orleans.
Without a 100-year flood since 1894, the city’s Web site has said another major flood is “a question of when and not if.”
Related link: Boulder Creek Flood Notebook
As bad as this current flooding is, it’s not the “big one” explains Eve Gruntfest, a research scientist at the Trauma, Health and Hazards center at the University of Colorado at Colorado Springs. Gruntfest says the National Weather Service has indicated this is a 10-25 year flood, as opposed to 100-year type event.
“We have extremes, but not that extreme,” Gruntfest says. “So I hope these don’t turn into many rainy days, saturated soils, and then a giant downpour. I don’t think that is forecast, thank goodness, like the situation in l999 in Venezuela that killed 30,000 people.”
After a possible round of heavy rain this afternoon, the forecast calls for slow drying in the coming days.
Here are some more videos/photos of the flooding, via Twitter:
Video: Flooded downtown Estes Park via Estes Park News on Facebook
Video: Along the river in Estes Park via Estes Park News on Facebook
— Gaelen Calhoun (@GaeCal) September 12, 2013
— David Harpe (@daveharpe) September 12, 2013
— Brandon Rittiman (@BrandonRittiman) September 12, 2013
@cshank27 via Instagram
— Elizabeth Jean Hall (@Elizabe07042011) September 12, 2013
More: Photos from Denver Post
Interactive map of flooding from ESRI: