Midwest and Southern Plains received beneficial rain

The heaviest precipitation this past week occurred across the Midwest and Southern Plains. Flooding rains developed from south Texas into the Gulf Coast region during and beyond the period considered in this week’s analysis.

Portions of Illinois and Indiana recorded precipitation totals 4 to 5 inches above normal. Over the past several weeks, persistent rainfall across the Midwest and central to southern Plains has contributed to widespread drought improvement.

Temperatures were near to above normal across much of the country. The coolest conditions were observed from the central Plains into the northern Rocky Mountains, where portions of Montana and Wyoming averaged 4 to 6 degrees Fahrenheit below normal. In contrast, the East Coast—particularly New England—as well as much of California and southern Nevada, experienced above-normal temperatures. Parts of New England recorded departures of 8 to 10 degrees above normal.

The U.S. Drought Monitor is jointly produced by the National Drought Mitigation Center at the University of Nebraska-Lincoln, the U.S. Department of Agriculture and the National Oceanic Atmospheric Administration. (Map courtesy of NDMC.)

Midwest

The Midwestern states continue to experience an active pattern lately, with another week of extensive rainfall and several severe weather episodes from Missouri and Iowa, east into Michigan and Ohio.

As such, more drought relief occurred from northeastern Missouri through northern Illinois.

Northern Missouri had the heaviest totals in the 5 to-10-inch range, wiping out the last remaining stand of abnormal dryness over the northeast part of Missouri. Long-term severe to extreme drought remained in the bootheel of Missouri, where long-term signals still reflect substantial rainfall deficits.

Other areas of drought expansion in the Midwest region occurred in northern Minnesota and northern Iowa, where long-term, persistent rainfall deficits continue to be a concern. In northern Minnesota, severe drought has been expanded north-northeastward toward the Canadian border to reflect the persistent and intensifying drought signal across the northern part of the state.

While southern and eastern Iowa has been experiencing substantial rainfall, the northern and western part of the state has been persistently dry. The lack of rainfall this past week in north-central Iowa warranted the introduction of moderate drought just south of the Minnesota border, according to a local agriculture extension report.

High Plains

Across the High Plains states, drought continues to persist across western Kansas and eastern Colorado. The most severe and exceptional drought areas extend from eastern Wyoming into western and northern Nebraska and far southern South Dakota.

Continued lack of rainfall and warmer-than-normal temperatures led to worsening drought conditions in the plains of eastern Colorado and small portions of northwestern Kansas. Exceptional drought was expanded across three counties in the Nebraska panhandle, where pastures and dryland wheat conditions are the poorest seen in decades, as a result of the record warm, dry winter followed by meager spring rainfall.

The agricultural impacts in western Nebraska were confirmed by drought indicators spanning the last six to 12months.

Other areas of degradation occurred this past week over North Dakota, especially the western half of the state. Moderate drought expanded southward along the Montana border as dry conditions intensified in western North Dakota. Abnormal dryness was introduced from southwest to north-central North Dakota due to recent drier-than-normal conditions.

The only improvements in the High Plains region are in central and eastern Nebraska. A couple swaths of 2 to 4 inches of rain fell this past week along the Interstate 80 corridor and into the southeastern part of Nebraska, which is presently free of any drought or abnormal dryness.

South

Across the southern states, many areas experienced widespread and substantial rainfall of 2–6 inches over the past week, especially southern and eastern Texas, eastern Oklahoma and northern Arkansas. Most areas of the deep southern states experienced drought improvement from all this rainfall.

The northeastern portion of the Texas Panhandle saw 2 to 4 inches rainfall over an area of exceptional drought, helping to relieve drought conditions with a small downgrade to extreme drought there. However, for the most part, extreme to exceptional drought conditions persisted across the Texas and Oklahoma panhandles, and much of western Oklahoma.

Despite weekly rainfall of 2 inches or more along the periphery of Arkansas, severe to exceptional drought continued to persist in much of the state due to the long-term rainfall deficits of the past several months.

The recent appreciable rainfall over eastern Oklahoma, combined with more heavy rains this past week, led to a large removal of abnormal dryness from Texas to southwestern Missouri.

Widespread heavy rainfall of 2 to 6 inches or more led to more drought coverage and intensity reduction across southern and eastern Texas, central Louisiana, and parts of western Mississippi.

West

There was not widespread precipitation across the region. However, portions of New Mexico, southern Montanaand northern Wyoming recorded above-normal precipitation.

Temperatures were mixed, with below-normal readings across northern portions of the region and above-normal temperatures farther south.

Moderate, severe, and extreme drought also expanded into western Montana, while extreme drought increased in coverage across central Wyoming.

Several weeks of wetter-than-normal conditions in New Mexico allowed for improvements to extreme drought across northeastern and southern portions of the state, although slight expansion occurred in northern areas. Improved short-term moisture conditions in western Colorado supported reductions in extreme drought, while degradation occurred across central and eastern Colorado.

The impacts of a dry winter and below-normal snowpack continue to affect Colorado and other parts of the region, where increasing numbers of waterways are experiencing low-flow conditions.

Looking ahead

During the next five to seven days, more heavy rainfall is expected in the Deep South, as a result of a Tropical Storm Arthur near the southeastern Texas coast as of this writing. Deep tropical moisture will stream northeastward from Arthur as it advances into the Southeastern states.

Current rainfall forecasts by the Weather Prediction Center also show the potential for several inches of rain from Oklahoma, Missouri and Arkansas,. Other areas of appreciable rainfall are forecast for parts of the Northeast and the eastern portions of the High Plains.

The Climate Prediction Center’s 6– to 10-day outlook shows that above-normal temperatures should prevail across much of the western U.S. and along the immediate Gulf coast into Florida. Below-normal temperatures are possible from the eastern portions of the High Plains, the Midwest, and into the Northeast states.

Meanwhile, precipitation is projected to be above normal across much of the Midwest and High Plains, possibly extending into the Northeast states. Near-normal rainfall is anticipated across the South and Southeast with below-normal precipitation expected in most of the West.

Brian Fuchs is with National Drought Mitigation Center.