South Region: According to ACIS, measured precipitation during the past 7-days was less than 0.5-inch over much of the South. Weekly temperature departures generally ranged between 4-10 degrees F above average. Significant 30-day precipitation deficits and near-record warm temperatures prompted the expansion of D0 across portions of Texas. In fact, the entire Texas drought depiction experienced another major overhaul this week.
Low stream flows have been an issue in the Texas Hill Country for several months already. The position of the impacts line was adjusted to approximately bifurcate the state into a western portion (now SL, with longer-term deficits appearing), and an eastern portion (still S). Across the deep South Texas counties of Willacy and northern Cameron, conditions were degraded this week from D1 to D2, based on stressed fields of cotton (despite ongoing irrigation), high KBDI levels (600-700), and a 120-day SPI blend. In Oklahoma, continuing degradation of conditions led to an expansion of both D0 and D1 in southeast parts of the state.
A few tweaks were made to the depiction in western Oklahoma as well, based on recent rainfall. Hot, relatively dry conditions prompted a broad expansion of D0 across most of Louisiana, western Arkansas, and adjacent portions of western and southern Mississippi this week. Current NLDAS soil moisture anomalies for the root zone (top one-meter) indicate values ranging from 1-3 inches below normal. Shreveport, LA, reported its warmest May on record, 78.4 degrees F, which supplanted the old record of 77.8 degrees F set back in 1933. Two areas of D1 were introduced in northwestern and south-central Louisiana this week. Topsoil moisture (Very Short to Short) for a few states include: Louisiana (73% this week, 55% last week), Arkansas (34%, 21%), Mississippi (22%, 14%) and for the Contiguous U.S. as a whole (28%, no change from last week). For Rangeland/Pastures, the percentages rated Very Poor to Poor this week compared to last week include: Louisiana (30% this week, 17% last week), Arkansas (6%, 8%), Mississippi (11%, 11%).
Looking Ahead: For the ensuing 5-day period (June 7-11, 2018), the northern and eastern CONUS are generally predicted to receive 0.5-1.5 inches of rain. Heavier amounts are forecast over portions of the western Corn Belt, the southern Great Lakes region, and the Florida peninsula. A relative maximum of 3-4 inches is possible in Iowa, likely due to nocturnal thunderstorm clusters (MCS) which are common at this time of year. Little to no precipitation is expected elsewhere during this period. For the subsequent 5-day period (June 12-16, 2018), CPC predicts elevated odds of above normal rainfall across the southern CONUS, with a weak tilt toward above running northward across the Mississippi Valley and eastern Great Plains region. Elevated odds of below normal rainfall are highlighted over the Northwest, the northern High Plains, and most of the Atlantic Coast states from Maine to Virginia.
Read more at http://droughtmonitor.unl.edu/