Summary

July 27, 2018 - During the period covering July 17-24, precipitation fell across a vast majority of the East, the heaviest of which flooded parts of Maryland, including the Washington D.C. area. Heavy rains also fell in parts of Florida, Kentucky and South Carolina. In the central U.S., moderate precipitation fell in parts of the High Plains while lighter rains provided little to no relief in parts of Kansas. The drought-stricken areas of Oklahoma and Texas saw little to no precipitation and triple digit temperatures, exacerbating drought conditions.

Northeast

Tropical moisture flowed in from the Atlantic, providing abundant moisture for a large area covering Maryland, central Pennsylvania, southern New York, and parts of New England. Washington Dulles International Airport broke its July daily precipitation record with 5.01 inches of rain on the 21st. The previous record was 3.71 inches set on July 11, 2013. Radar estimates for the 7-day period were as high as 10-12 inches in Maryland. Since the beginning of June the Baltimore-Washington International Airport has received nearly 18 inches of rain, surpassing 1889 for its wettest June/July total on record. Abnormal dryness was removed in Virginia and Maryland but remained in Delaware and southern New Jersey where lighter precipitation fell. Moderate drought (D1) was removed in Massachusetts where streamflows have rebounded. In contrast, moderate drought was expanded in upstate New York where 30-day precipitation deficits exist. Abnormal dryness was extended out through northern New York.

Southeast

Tropical moisture flowed in from the Atlantic, providing abundant moisture for much of the mid-Atlantic region resulting in generally above normal precipitation for much of the region during the USDM period. Some locations in coastal South Carolina and north central Florida received between 8 and 9 inches during the 7-day period. Much of Georgia and the western Carolinas received 1-3 inches from summertime convection.. Precipitation totals in northeast Virginia approached 10 inches. Abnormal dryness continued for some of the central Carolinas; however, it was contracted in areas where this week’s heaviest precipitation fell.

Midwest

The Midwest experienced a mixture of both above- and below-normal precipitation amounts during the USDM week. In eastern Kentucky and Tennessee and along the border of Ohio and Indiana, precipitation amounts were the highest. As much as 5 inches of rain fell in those areas. Farther west, dryness prevailed. Little to no rain was measured across much of Illinois, eastern Missouri and western Iowa. Precipitation totals in those areas were 25-50 percent below normal for the 30-day period. The USDA reported that topsoil conditions were 77 percent short to very short in Missouri while subsoil conditions were 72 percent short to very short. Farmers in Missouri are having to bail the corn crops since little to no ear development is widespread. In Michigan, topsoil was rated at 68 percent short to very short and subsoil conditions were 72 percent short to very short. Local reports indicated that soybeans in parts of Michigan were less than 2 feet high and the leaves were flipped and showing their undersides. USDA reported that soybean conditions were 20 percent poor to very poor across the entire state. D0 drought was expanded to cover most of Lower Michigan and D1 was expanded slightly in eastern Michigan and introduced in southern Michigan. Abnormal dryness was also introduced in central Wisconsin and southeast Illinois, and expanded in parts of northern Minnesota.

South

Across much of the South, no measureable rains fell during the period. This was especially true for Texas, Oklahoma, and Louisiana. Arkansas, Mississippi and Tennessee received moderate precipitation – generally less than 2 inches, although eastern Tennessee had locally higher amounts of 3-5 inches during the period. Departures during the last 30- and 60-days were generally about 10-25 percent below normal. One of the driest parts of the region was around the borders of Arkansas, Louisiana, Oklahoma, and Texas where two separate areas of extreme drought (D3) were introduced this week. Extreme drought was also introduced in a small area to the west of Dallas, Texas. The drought has been exacerbated by extreme heat. Many locations in Texas have had two straight weeks of maximum temperatures reaching 100 degrees F or more. On July 23, Waco, Texas recorded an all-time high temperature of 114 degrees F. The heat also stretched into Louisiana where, on the 22nd, Shreveport hit 108 degrees F, besting its monthly record. Conditions in some parts of Texas are being compared to the drought of 2010 and 2011. One rancher reported that he had only had 6 inches of rain since January and another reported just 4.5 inches. The persistent heat and dryness has browned grasses, dried up stock tanks and ponds and increased fire danger.