Billion dollar weather events in the U.S. during 2011. Count indicated by size of bars (adapted by author to include Missouri River flooding in 2011), damages indicated by lines (damage numbers in 2011 do not include Missouri River flooding). (From NOAA, adapted by author)

Add the flooding of the Missouri River to the list of billion dollar weather disasters in the U.S. in 2011. The economic toll from that historic flood - which is ongoing - brings the total number of billion dollar weather events in 2011 to nine, tying 2008 for the most on record since 1980. And hurricane season still remains.

Although NOAA has not yet officially listed the Missouri River flooding as a billion dollar event, Angela Fritz, atmospheric scientist at Weather Underground estimates the flood has produced at least $2-4 billion in damages.

Fritz points out that U.S. Army Corps of Engineers said damage to levee and dam systems alone could reach $1 billion. That figure doesn’t include damages to roads or the 500,000 flooded acres in seven states.

“The $2-4 billion estimate is a definitely a low-ball estimate,” she said.

NOAA compared the Missouri River flood to the Great (Mississippi River) Flood of 1993, which caused $25 billion in damages.

Although river levels have recently receded some, the flood risk remains high NOAA cautioned.

“The sponge is fully saturated – there is nowhere for any additional water to go,” said Jack Hayes, Ph.D., director of NOAA’s National Weather Service. “While unusual for this time of year, all signs point to the flood threat continuing through summer.”

In its June State of the Climate report, NOAA said heavy precipitation on top of deep snow produced record releases from Fort Peck Reservoir in Montana, by far the greatest flows on the Missouri River since the dam was closed off in 1937.

A pickup truck is parked on a dry spot of road in Fort Calhoun, Neb., Wednesday, July 6, 2011, amid flood waters from the swollen Missouri River. (Nati Harnik/AP)

Flooding along the Missouri River persisted through the month with major flooding in western Iowa and northwest Missouri. Moderate to minor flooding occurred further down river in Missouri. Interstate 29 in western Iowa and northwest Missouri was closed in multiple locations due to water over the roadway. Bridges across the river were closed due to water on the approaching roads or concerns about their ability to withstand the rushing waters. For more than 100 miles (161 km) from south of Council Bluffs, Iowa to north of St. Joseph, Missouri, all traffic bridges were closed at some point in the month. Levees were overtopped or breached in southwest Iowa and northwest Missouri causing evacuations of several towns and the surrounding rural areas. Freight and passenger train service was disrupted across and along the river. In addition to the many homes and businesses affected, thousands of acres of farmland were under water and unlikely to produce a crop this season.

The other eight billion dollar weather events of 2011 are:

1) ‘Groundhog Day Blizzard’ Jan 29-Feb 3.
2) Midwest/Southeast Tornadoes April 4-5.
3) Southeast/Midwest Tornadoes April 8-11.
4) Midwest/Southeast Tornadoes April 14-16.
5) Southeast/Ohio Valley/Midwest Tornadoes April 25-30.
6) Midwest/Southeast Tornadoes May 22-27.
7) Texas Drought & Wildfires Spring-Summer 2011.
8) Mississippi River flooding Spring-Summer 2011

For more information about these events, refer to our previous update on 2011 U.S.billion dollar weather disasters...

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