Just as dryness (D0) and moderate to severe drought (D1 to D2) was ramping up across the south-central U.S., heavy rain struck many areas. In particular, streaks of heavy rain across Texas, Oklahoma, Louisiana, and Arkansas led to significant reductions in the coverage of dryness and drought. Some of the heaviest rain, locally 4 to 8 inches or more, fell from north-central Texas into east-central and northeastern Oklahoma. Still, the rain largely bypassed a few areas, including the lower Rio Grande Valley, leaving the drought designation intact or even leading to local deterioration. On May 21, the U.S. Department of Agriculture noted that topsoil moisture was 100 percent very short to short in the lower Rio Grande Valley. Read more at droughtmonitor.unl.edu…