May 1-8, 2001

The period May 1-8 was marked by a continuation of the April pattern of heavy precipitation in the Upper Mississippi Basin and considerable dryness elsewhere in the Midwest to the south and east. Precipitation totals exceeded 4 inches in northern Iowa and southern Minnesota, while most areas to the east received less than 0.75 inches for the period (Figure 6). A quasi-stationary frontal boundary draped across Iowa, Minnesota, and Wisconsin, bringing along short waves as well as an intense synoptic scale low toward the end of the period. More rain was received in the flood-affected areas from convection along the stationary boundary. The intense cyclone, while traveling north into Canada, whipped a cold front across the entirety of the Midwest, finally bringing some much needed rain to the eastern half of the region. Unfortunately, most of the eastern Midwest was still far below average in precipitation for the period (Figure 7), exacerbating drought conditions. In addition, temperatures were well above normal throughout the dry areas (Figure 8), further enhancing evapotranspiration and causing the drought to intensify. The May 8 U.S. Drought Monitor placed parts of southeastern Missouri, southern Illinois and Indiana, and western Kentucky in severe drought status (Figure 9, National Drought Mitigation Center). The USDA reported that the majority of soils were short or very-short of soil moisture in these areas, and corn germination and early growth was being affected.