National Drought Monitor

This U.S. Drought Monitor (USDM) week saw continued improvement in drought-related conditions across areas of the Midwest (Michigan, Ohio, Indiana, Illinois, Iowa, Minnesota), central and northern Plains (Kansas, Nebraska, Dakotas, eastern Montana), South (Texas), and in the Desert Southwest (New Mexico). During the past week, the most significant rainfall accumulations were observed across areas of Kansas, Missouri, Iowa, and Minnesota, where they ranged from 3 to 7+ inches. Elsewhere, short-term precipitation shortfalls (past 30 to 60 days) led to continued expansion of Abnormally Dry (D0) areas across the Southeast states including the Carolinas, Georgia, and Alabama as well as the introduction of isolated areas of Moderate Drought (D1) in Alabama, Georgia, and South Carolina where agriculture-related drought impacts are being reported. In the South, drought conditions continued to improve in western portions of Texas as well as in areas of eastern New Mexico where monsoonal storms have provided some minor relief to areas experiencing long-term drought. In the West, conditions continued to deteriorate across the Pacific Northwest (Oregon, Washington, Idaho) and areas of the Intermountain West (Wyoming, Utah, and Colorado), while areas of eastern Montana saw improvement in drought in response to precipitation events during the past few weeks. In terms of reservoir storage in the West, California’s major reservoirs continue to be at or above historical averages for the date (July 29), with the state’s two largest reservoirs, Lake Shasta and Lake Oroville, at 105% and 116% of average, respectively. In the Southwest, the U.S. Bureau of Reclamation is reporting (July 27) Lake Powell at 32% full (46% of average), Lake Mead at 31% full (51%), and the total Colorado system at 39% of capacity (compared to 44% of capacity the same time last year).

Southeast

During the past week, light-to-moderate rainfall accumulations were observed across the southern extent of the region with the heaviest accumulations (ranging from 2 to 4 inches) occurring in isolated areas of Georgia and Florida. However, pockets of short-term dryness (2 to 6 inches of rainfall deficits during the past 30-day period) led to the introduction and further expansion of Abnormally Dry (D0) areas in the Carolinas, Georgia, and Alabama as well as areas of Moderate Drought (D1) in southwestern portions of Alabama and Georgia. In these areas, streamflow and soil moisture levels are declining and the National Drought Mitigation Center’s Condition Monitoring Observer Reports (CMOR) system has received some drought-related impact reports in the agricultural sector during the past 30-day period. In terms of average temperatures for the week, the region experienced above-normal temperatures, with the greatest anomalies (4 to 6 degrees F) observed across areas of northern Virginia, the Carolinas, northeastern Georgia, and northern and central Florida.

South

On this week’s map, improvements were made in areas of South Texas and the Trans Pecos region of Texas in response to above-normal precipitation during the past 30-120 days. In these regions, improvements were made in numerous drought categories (D1-D3). In other areas of the region, degradations occurred in southwestern Oklahoma, northern Mississippi, and central Tennessee, where rainfall has been below normal during the past 30 to 60 day period. For the week, average temperatures were above normal in the eastern and northern areas of the region, with anomalies ranging from 2 to 8 degrees F. Conversely, the western extent of the region, including areas in the southern half of Texas, experienced temperatures ranging from 1 to 4 degrees F below normal.

Midwest

Another week with scattered shower activity across drought-affected areas of the region led to continued improvements on the map from Minnesota to Ohio. For the week, rainfall accumulations ranged from 1 to 5 inches, with the heaviest amounts observed in isolated areas of northern Missouri, eastern Iowa, southern Minnesota, central Illinois, and northern Indiana. On the map, improvements were made in Minnesota, Iowa, Wisconsin, Illinois, Indiana, Michigan, and Ohio. Despite recent rainfall events and overall improving conditions across areas of the region, negative soil moisture anomalies are continuing to show up in northern Illinois, northeastern Indiana, and southern Michigan on several soil moisture monitoring data products. For the week, average temperatures were above normal (2 to 10 degrees F) across the region.

High Plains

On this week’s map, improvements continued from Kansas to North Dakota after another week of scattered shower activity with light-to-moderate accumulations. During the past 30 days, drought-related conditions have improved significantly in northern Kansas, eastern Nebraska, southeastern and southwestern South Dakota, and southwestern North Dakota as evidenced in a variety of drought monitoring products including streamflows, soil moisture, and vegetation health indicators. However, conditions have degraded in other parts of the region, including central South Dakota and northern North Dakota. For the week, average temperatures were generally above-normal average (1 to 6 degrees F) across the region, with eastern portions experiencing the largest departure, while far western portions of the Dakotas observed temperatures 1 to 4 degrees F below normal.

Looking Ahead

The NWS Weather Prediction Center (WPC) 7-Day Quantitative Precipitation Forecast (QPF) calls for generally dry conditions across much of the western U.S. except for some light shower activity (accumulations generally <1 inch) across areas of the Rockies (Idaho, Montana, Wyoming, Colorado) and mountain ranges of New Mexico. East of the Rockies, light-to-moderate accumulations (ranging from 1 to 4 inches) are expected across areas of the Plains states with the heaviest accumulations expected in western Oklahoma. In the lower Midwest, Mid-Atlantic, South (Gulf Coast areas), and portions of the Southeast, 1 to 5+ inch accumulations are forecast, with the heaviest accumulation expected along the coastal plains of Carolina and Georgia. The Climate Prediction Center (CPC) 6-10-day outlooks call for a moderate-to-high probability of above-normal temperatures across the Desert Southwest, southeastern portions of the Intermountain West, Plains, Midwest, New England, South, and southern portions of the Southeast region. In contrast, below-normal temperatures are forecast for areas of the West, including southern California, the Great Basin, and Pacific Northwest. In terms of precipitation, there is a low-to-moderate probability of above-normal precipitation across the Pacific Northwest, northern portions of the Intermountain West, northern Plains Midwest, Mid-Atlantic, and Southeast. Elsewhere, below-normal precipitation is expected across the southern half of the western U.S., southern Plains, and Texas.