During April, severe flooding developed from the Mid-South into the Ohio Valley. At the same time, a snowmelt-induced flood crest moved along the upper and middle Mississippi River. By month's end, floodwaters converged on the confluence of the Ohio and Mississippi Rivers, eclipsing the region's high-water marks established in February 1937. Monthly rainfall totals of 1 to 2 feet were common in the flood-affected areas. A pair of historic tornado outbreaks accompanied the storminess, battering the South from April 14-16 and 25-28.
Meanwhile in the northern Corn Belt, cool, damp weather and soils hindered the start of the spring planting season. Due to the Midwestern fieldwork delays, only 13 percent of the United States acreage intended for corn was planted by May 1 - the Nation's slowest start since 1995 (11 percent planted).
Cool, damp conditions also prevailed across the northern Plains and the Northwest, slowing winter wheat development and hampering spring planting operations. Cool conditions were also noted as far south as California.
In contrast, heat and drought continued to severely stress pastures, winter grains, and emerging summer crops on the southern Plains. By May 1, approximately three-quarters of the winter wheat crop was rated in very poor to poor condition in Oklahoma (77 percent) and Texas (74 percent), along with nearly half of the crop in Colorado (46 percent) and Kansas (45 percent).