Temperature and Precipitation Anomalies.

April was cooler than normal in the Midwest for the first time since October 1999 (Figure 1), but no state was more than 2 Deg F below average, and no state ranked among the 20 coolest months of April. Only portions of the northern Midwest were above normal in temperature, especially in northern Minnesota. The most below normal temperatures were found in southern Illinois and Kentucky, where storms passing through to the south reduced incoming solar radiation and left moist surface layers behind. The Midwest had its 45th coolest April in 106 years.

The drought affecting large portions of the Midwest continued to intensify, especially in Missouri, which endured its driest April in the 106 year instrumental record (Figure 2). Other western Midwest states also received little rain, with Minnesota and Iowa having their 18th and 26th driest April, respectively. Only Kentucky and Ohio received above normal statewide averages of rainfall in April. However, a narrow strip of southern Wisconsin, northern Illinois, and southern Michigan received considerably above normal rain totals when two heavy rain producing systems followed the same path at mid-month. Even in the generally more moist eastern Midwest, places in northwestern Michigan and central to southern Indiana received less than 75% of normal rainfall. Overall, the Midwest experienced its 27th driest April in 106 years.

Climate and Agriculture.

The fairly dry conditions in March and April have led to an expansion of severe drought conditions into most of Missouri and southwestern Illinois. Surface soil layers are actually quite adequately moist in the eastern and central corn belt, belying the strong soil moisture deficits still existing at lower depths in the soil. The western half of the Midwest, on the other hand, is already undergoing topsoil drying, especially in Missouri. The table below illustrates the topsoil moisture survey results of the USDA for May 1.

State	Very Short	Short	Adequate	Surplus
Illinois	5	27	63	5
Indiana	6	18	67	9
Iowa	23	39	38	0
Kentucky	0	7	74	19
Michigan	10	17	63	10
Minnesota	13	40	44	3
Missouri	28	47	25	0
Ohio	0	4	81	15
Wisconsin	4	32	62	2

Farmers are planting corn at a rapid rate well ahead of normal due to generally favorable working conditions. Even though temperatures have been below normal, only on one or two days after mid-April did temperatures reach frost levels in the southern half of the Midwest. While top soil moisture is present, very few places are at surplus to the point of impeding farm equipment. Farmers are generally following normal plans based on economic considerations, but acknowledging some increased uncertainty with regards to outcomes. In the Midwest, the lack of rain in the spring is especially problematic, as this is usually when much of the subsoil moisture recharge occurs.

Other impacts are also present from the drought in the Midwest. The capitol city of Illinois, Springfield, just passed an emergency water conservation ordinance due to the low levels of Lake Springfield, the city water supply. Several water bodies in Missouri are also very low for the time of year, including Mark Twain Lake in Monroe City, Missouri. Smaller municipalities dependent on surface water supplies are likely to come under increasing influence of the drought, as long range forecasts by the Climate Prediction Center are still calling for drier and warmer than normal conditions in the Midwest this growing season.

Extreme Events and Impacts.

The month of April was very quiet with regards to severe weather in the Midwest; only one notable severe weather outbreak affected the region. A low pressure system and strong cold front delivered severe weather to the Midwest on April 20. About 175 severe weather reports were logged by the Storm Prediction Center (Figure 3, from the Storm Prediction Center). In Illinois alone, 10 tornado touchdowns were reported, with at least 8 confirmed, but no one was seriously injured in Illinois. One person died in central Kentucky due to injuries sustained when straight line winds caused a tree to fall on her mobile home. Some additional notable impacts are listed below (information was derived from a variety of media sources).

Illinois	Trucks overturned and isolated buildings destroyed; one 430 foot radio station tower toppled; 10,000 without power in central IL and 9,000 without power in northeast IL; street and basement flooding in Chicago; hundreds of flights canceled and many delayed up to six hours at O'Hare; many school children in central Illinois under tornado warnings for up to 1.5 hours.
Indiana	Mobile homes moved off of foundations in Bloomington (1 minor injury); 1.75-inch hail stones fell in several places; trees downed; isolated power outages.
Kentucky	Several mobile homes overturned; one mobile home owner crushed to death by a falling tree; many trees downed in central KY by straight line winds; isolated barn and house damage and power outages.
Michigan	Cancellation of 182 flights from Detroit Metro Airport, with many flights delayed hours; flooded roads cause a 15 car and 2 semi chain reaction collision on I-96; lightning struck 2 men in Dexter, with both surviving; 37,000 in Lower Michigan lost power for hours.
Ohio	Many trees down; isolated power outages; some buildings damaged; flash flooding was common along small creeks already running high from earlier rains.

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