Across the Corn Belt, cool but dry weather from the Mississippi Valley westward favors a limited return to fieldwork, following recent rainfall. However, widespread lowland flooding persists in northern and central Illinois and portions of neighboring states. Early Tuesday, the Illinois River at Morris, Illinois, crested 8.85 feet above flood stage—less than an inch below the high-water mark established April 19, 2013. Meanwhile, rain showers linger across the eastern Corn Belt.
On the Plains, mostly sunny, dry weather favors fieldwork and crop development. However, excessive wetness remains a problem in eastern sections of the northern Plains. In North Dakota, for example, 94% of last year’s corn crop had been harvested by May 17. On the same date, planting progress in North Dakota for sunflowers, soybeans, corn, barley, spring wheat, oats, and sugarbeets stood at 2, 9, 20, 33, 41, 47, and 66%, respectively, compared to 5-year averages of 15, 35, 60, 76, 76, 70, and 96%. In contrast, topsoil moisture on May 17 was rated 59% very short to short in Colorado, along with 53% in Texas.
In the South, a significant rainfall event is underway in eastern sections of Kentucky and Tennessee, as well as parts of Virginia and the Carolinas. Meanwhile, spring fieldwork delays continue in the northern Mississippi Delta, where Arkansas led the region on May 17 with topsoil moisture rated 45% surplus. On that date in Arkansas, soybean, cotton, and rice planting were 47, 47, and 76% complete, respectively, compared to 5-year averages of 57, 71, and 88%.
In the West, warm, dry, breezy weather in the Four Corners region is maintaining an elevated wildfire threat. In contrast, cool, showery weather lingers in the northern Great Basin and the Northwest. Precipitation has mostly subsided across the Sierra Nevada, following a late-season snowfall.
A pair of slow-moving storm systems will maintain showery conditions in several areas, including northern sections of the Rockies and High Plains, the southern Appalachians, and the southern Mid-Atlantic States. In the latter region, 5-day rainfall totals of 4 to 6 inches or more could trigger flooding. As the week progresses, showers and locally severe thunderstorms will erupt across the nation’s mid-section, where 5-day totals could reach 1 to 3 inches or more across the central and southern Plains. In contrast, mostly dry weather will prevail through week’s end in New England and the Southwest. Late in the week, warmer weather will replace previously cool conditions across much of the central and eastern U.S.
Looking ahead, the 6- to 10-day outlook calls for the likelihood of near- or above-normal temperatures nationwide, except for cooler-than-normal conditions in parts of Texas. Meanwhile, near- or above-normal rainfall across most of the country should contrast with drier-than-normal weather across the interior Northwest and along the middle and northern Atlantic Coast.