Substantial recent flooding in the Midwest was caused by heavy precipitation that fell not only in June, but also throughout the first half of 2008. The NOAA Midwestern Regional Climate Center (MRCC) found that 286 National Weather Service Cooperative Observer Network stations reported precipitation totals for the first half of 2008 that ranked within their top five records of the January-June period since the late 1800s in some cases.
"More than 100 individual stations tied or exceeded their January through June precipitation records in the Midwest region this year, which is an extraordinary 11% of stations with observations available," explained MRCC Regional Climatologist Mike Palecki. "Only a third as many Midwest stations achieved their current record in 1993, another year of great floods (although in 1993 the heaviest rainfall occurred in July)."
Some of the precipitation records set during June include:
|
Location
|
June Total (inches)
|
Old Record and Year
|
| |
|
Martinsville, IN
|
20.11
|
9.47" in 1998
|
|
Baraboo, WI
|
17.17
|
10.65" in 1949
|
|
Mt. Vernon, MO
|
16.03
|
12.56" in 2007
|
|
Hutsonville, IL
|
15.30
|
9.09" in 1999
|
|
Decorah, IA
|
14.10
|
11.80" in 1993
|
|
Washington, OH
|
11.14
|
9.40" in 1928
|
|
Lake City, MI
|
10.66
|
7.10" in 1967
|
Top 5 Precipitation Totals in Midwest,
June 2008
(Click to Enlarge Image)
In 1993, record precipitation during the first half of the year was largely confined in the Midwest to states surrounding Iowa, said Palecki. The early 2008 precipitation pattern caused heavy flooding both in and around Iowa and in the Ohio River Valley. Fortunately, top five ranking rain totals in June were less common in the Ohio Valley (Fig. 2), and not found at all over the southern tributaries to the Ohio River.
"The tremendous flooding resulting in Southern Indiana from a small area of intense rainfall indicates what could have happened more broadly in the Ohio Valley if the precipitation pattern had spread further east during June," Palecki added.
The locations with top five precipitation totals in June 2008 are clustered in an area similar to those affected in June 1993, although oriented differently. In June 1993 the affected locations were oriented from northwest to southeast across the region centered on eastern Iowa, while the June 2008 pattern stretched from southwest to northeast.
"This may indicate that June weather patterns triggering the two great floods were similar, but not exactly the same," said Palecki, who added that a study of these differences is underway.
The current status of precipitation, temperature, and other climate conditions can be monitored on the MRCC's "Midwest Climate Watch" web site, http://mrcc.isws.illinois.edu/cliwatch/watch.htm
The NOAA Midwestern Regional Climate Center is a cooperative program of the Illinois Water Survey and the National Climatic Data Center (National Oceanic and Atmospheric Administration, U.S, Department of Commerce).
National Weather Service Cooperative Observer Network precipitation stations having a Top 5 precipitation total for June 2008. Locations with stars tied or exceeded previous records, while the locations with dots are ranked second to fifth wettest on record. All stations reported at least 75% of the time, had 30 years or more of records, and were compared to all station data since 1895.