US Drought Monitor and Summary, Aug. 23, 2019

Source: droughtmonitor.unl.edu
Data valid 8-20-19 | May released 8-22-19
This Week’s Drought Summary: The United States is in the thralls of summer, and with that can come heat, flash droughts, and occasional, if not frequent, thunderstorm activity. Several areas of the U.S. experienced extreme heat this past week, particularly notable across much of the South and in the East. Parts of western Texas and eastern New Mexico were 6-10 degrees F above their typical averages, with little rainfall to speak of in much of the region. On the other hand much of the northern tier of the U.S. into the Upper Midwest was cool for this time of year, although precipitation amounts there were a mixed bag. In the Southwest, the North American monsoon continues to fail, worsening conditions in areas that had received more than ample precipitation over the winter and spring. To the north, south central Alaska continues to see record or near-record heat and dryness, and conditions are deteriorating quickly there, with severe impacts.

South: Aside from isolated and scattered rains, most of the area was very hot and dry, with daytime temperatures climbing to near or above 100 degrees F over portions of the region. Nighttime temperatures did not help alleviate the heat stress in places. Along the northern Gulf Coast, Galveston, Texas — which had never observed a minimum temperature above 85°F since its records began in 1874 — has recorded three to date this month: on Aug. 8, 12, and again on Aug. 18. Overall, there was some drought relief in a few spots in the South, but mostly there was drought expansion across the area where changes were made this week. There is a flash drought in north Central and northeast Texas, with some stations that are 10 inches above normal for the year, but 8 inches below normal for just the past two months. In eastern Texas, abnormally dry conditions (D0) were expanded across much of the area. Reported rainfall in areas was only 20 percent of normal. The D0 in far east Texas expanded eastward into extreme southwestern Arkansas where there have been reports of a sharp drop off in the green up along the interstate across southern Miller County, with some exposed areas browning quickly, and in northwestern Louisiana where reported precipitation at some stations has been just 50-70% of normal over the past two months. In Oklahoma, much of the southwest has seen less than 25% of its normal precipitation over the past two months, and less than 50% over the past three. Severe and moderate drought were expanded here and a couple of pockets of extreme drought (D3) were introduced to the west in the Texas Panhandle.

Looking Ahead: Over the week beginning Aug. 20, according to NOAA’s Climate Prediction Center, dry conditions are expected to continue across much of the western half of the continental U.S. Some heavy rain may fall over parts of the Midwest and Southeast, with as much as five inches in areas of southern Iowa, northern Mississippi, eastern Nebraska, and parts of the Carolinas. Southern Louisiana may see up to seven inches.
Looking further ahead to Aug. 25-29, below-normal temperatures are favored across parts of eastern Montana, the Dakotas, Nebraska, Kansas, Minnesota, Iowa, and Missouri, while above-normal temperatures are forecast for parts of the Southern Plains and the Southwest. There are enhanced probabilities of above-normal temperatures for most southern coastal locations of Alaska due to above-normal sea surface temperatures. Near to below-normal precipitation is possible for the west, although parts of Southern California may see above-average rainfall. Rainfall may be above normal across the central and eastern U.S., except for parts of the Northeast. Above-normal precipitation is favored across northern and eastern Alaska, but may be below-normal across southwestern mainland Alaska and the Aleutians, where drought conditions prevail. Please note the forecast confidence for this period is average, according to CPC.