Martell: Widespread Flooding Threatens Midwest Crops

By: Gail Martell

June  23,  2014

Gail Martell has been working as an agricultural meteorologist for 30 years. She began analyzing the relationship between weather and crop production with EF Hutton's New York Commodity Department in the late 1970s as the first Wall Street meteorologist. She has been a featured speaker with the National Association of Wheat Growers, the Alberta Grain Growers, the Illinois Farm Bureau and Pro Farmer seminars.. Martell served on the Midwest Governor's Commission on Drought in 1988 and was an invited El Nino specialist at the 2002 Agricultural Outlook Forum sponsored by USDA. Martell has a Master's Degree in Meteorology from the University of Wisconsin, Madison writing her thesis on The Midwest Drought of 1983 and Its Impact on U.S. Corn Production. Click here for more information on her weather services.

Widespread Flooding Threatens Corn and Soybeans, One of Wettest Junes on Record

Widespread flooding has developed in the Midwest, threatening 35-40% of corn and soybeans. Midwest rainfall last week totaled 3-5 inches. A horizontal weather front stalled in the Upper Midwest leading to recurring strong showers and thunderstorms. The heaviest rainfall developed from South Dakota to southern Wisconsin, and also including southern Minnesota, northern Iowa and north Illinois.


This is prime corn and soybean land threatening 38% of the United States crop. June rainfall to date has reached 5.9 inches threatening to break a record. The wettest June on record back to 1895 occurred in 2010 with 7.2 inches.

Flooding has washed nutrients out of the root zone. Producers may reapply fertilizer once fields have dried out. However, growth in corn and soybeans has been stunted from standing in water. Sunshine also been lacking with persistent cloudiness. Pockets of very heavy rainfall 5-6 inches have developed also in Missouri, Illinois, Indiana and Ohio.


Kansas wheat harvesting has come to a grinding halt with excessive June rainfall. Wheat growers were happy for heavy rain to begin, with replenishing parched fields in the wake of historic drought. However, in late June, heavy rainfall has caused flooding. Crop damage is reflected in declining wheat conditions, 63% of Kansas wheat now rated poor-very poor, up from 56% in mid May. Only 2% of Kansas wheat was harvested, up to June 15.

More Rain Still Coming

Wet is the watchword this week as above-normal rainfall is predicted to continue. Strong showers that hit Kansas overnight have dropped southward into Oklahoma and Texas. Harvesting in the two southern Plains wheat states is further advanced, compared to Kansas, though 40-50% of the crop was still in the field June 15.

The rainfall forecast continues very wet. Midwest corn and soybeans would receive at least .75 inch of rainfall this week, but up to 2-4 inches locally. There are two major areas of heavy rainfall predicted this week, on in the Upper Midwest (South Dakota and Minnesota), and a second swath from central Missouri through Illinois into central Indiana and Ohio.


Strong showers would be enhanced by a moist air stream from the Gulf of Mexico circulating up into the U.S. heartland. Showers are favored to begin in a trough of low pressure extending from Arkansas and Missouri up to Michigan and including Illinois, Indiana and Ohio.


More thunderstorms and heavy rain are expected later in the week Wednesday and Thursday in Iowa, Minnesota, Wisconsin, Missouri and Illinois. The forecast this week is wetter than 6-10 day forecast indicated. This is what happens with a strong monsoon circulation, as unstable air is carried up into the U.S. heartland. The North America monsoon is not always pronounced, sometimes inactive, but this summer it is very strong.

Temperatures this week are expected to be near average in the U.S. heartland, compared to the very warm conditions last week.