Broad drought improvements continued across parts of the South for the second week in a row as the ongoing effects of record-setting rainfall over the last two weeks became apparent. The North American Monsoon also continued to provide much-needed rainfall in the Southwest, leading to additional improvements across much of the region. The Midwest saw a mix of improvements and degradations due to locally heavy rain.
South
Rainfall totals over the past two weeks once again led to broad 1- and 2-category improvements across large parts of the South. For the second week in a row, all states in the region showed improvements as the effect of the rainfall became apparent in drought indicators such as soil moisture, streamflow and vegetation. Rainfall records show that the previous two weeks ranked in the top 10 wettest for this time of year in many locations in the region. Some of these records go back over 100 years.
Drought remains in areas that missed out on the recent heavy rains and those in which rainfall deficits still exist at 90-plus days so that deeper soil moisture, shallow groundwater and streamflow indicators have yet to recover. Extreme (D3) drought expanded in northern Oklahoma in the areas that missed out on the heavy rain. Rainfall deficits of nearly 6 inches have continued to dry out soils and stress vegetation.
Midwest
Spotty, heavy rain fell across the Midwest this week, leading to a mix of drought improvement and deterioration. Above-normal rainfall led to 1-category improvements across parts of eastern Minnesota, Wisconsin, Michigan, central Iowa, Illinois and Indiana. The much-needed rainfall helped replenish soil moisture and streamflow. Moderate (D1) and severe (D2) drought expanded in northwest and southeast Iowa where rainfall deficits of 6 to 8 inches over the last 90 days have dried out soils, reduced streamflow and strained vegetation.
High Plains
Warm, dry conditions continued across much of the region with the Dakotas, Nebraska and Kansas seeing some areas of worsening conditions. In Nebraska and Kansas, all levels of drought expanded as short-term precipitation deficits, on top of long-term dryness, continued to deplete soil moisture and stress vegetation. Exceptional (D4) drought expanded in the southwest where rainfall deficits of over 3.5 inches have occurred over the last 90 days. Extreme (D3), severe (D2) and moderate (D1) drought expanded in the eastern half of Nebraska where rainfall deficits of 3 to nearly 7 inches have occurred over the last 90 days.
Other areas of Nebraska seeing degradations include north-central Nebraska, where D2 expanded, and the Panhandle, where D1 expanded. Similarly, Kansas also saw large areas of deterioration. In the western half of the state, D1, D2, D3 and D4 expanded where rainfall deficits near 5 inches occurred over the last 90 days. In the east, improvements were made to D1 where the heaviest rain fell over the last 2 weeks. Improvements were also made in eastern South Dakota to D1 along a band of heavy rain last week.
West
The North American Monsoon continued to provide excellent rainfall in the Southwest. Many areas in the region only receive about five inches of rain annually, but a few spots have nearly equaled this annual average in the last two weeks alone. Drought conditions improved in areas receiving the heaviest rain. Many drought indicators, including soil moisture, streamflow and well data, are responding to the rainfall. Improvements were made to moderate (D1) and severe (D2) drought in Arizona, extreme (D3) drought in Southern California and eastern Utah, and D2 and D3 conditions in eastern New Mexico. To the north, Montana saw an expansion to abnormally dry (D0) and D1 areas as conditions began to rapidly deteriorate. Low rainfall, combined with high evaporative demand, has lowered streamflow and stressed vegetation there.
