This week’s drought summary: This U.S. Drought Monitor (USDM) week saw an active weather pattern with severe weather observed across portions of the central and southern Plains, Texas, mid-South, Midwest, and the Northeast. In Texas, 7-day rainfall accumulations ranged from 2 to 10+ inches leading to significant improvement in drought-related conditions across the state. Likewise, areas of northeastern Colorado and portions of the central Plains received much-needed rainfall (2-to-4-inch accumulations) leading to improvements on the map. Out West, 83% of the region is currently in moderate-to-exceptional drought with the most severe conditions centered on the Four Corners states, California, and Nevada. In California, conditions deteriorated on this week’s map in response to a combination of factors including back-to-back dry water years, above-normal temperatures, below-normal snowpack, and drought impacts (agricultural, ecosystem health, water supply, recreation).
South: On this week’s map, widespread improvements in areas of drought were made across Texas (and southern and eastern Oklahoma) in response to significant precipitation accumulations (ranging from 2 to 10+ inches) with areas along the Texas Gulf Coast and the Hill Country receiving the heaviest accumulations. The slow-moving front that entered the region last week brought severe storms with frequent lighting, tornados, and softball-sized hail that caused extensive property damage with damage estimates expected to exceed $3 billion. This week’s rainfall significantly improved soil moisture levels across much of Texas, but negative soil moisture anomalies remained across the Trans-Pecos and the Texas Panhandle regions according to the NASA Crop-CASMA. According to Water Data for Texas (May 4), monitored water supply reservoirs are currently 83.6% full, with most of the reservoirs in the eastern half of the state ~80% to 100% full and reservoirs in the western half of the state generally <50% full. Average temperatures for the week were below normal (2 to 10 deg F) in the Trans-Pecos, Edwards Plateau, and southern High Plains regions of Texas, whereas the rest of the region was above normal with the greatest anomalies (5 to 15+ deg F) observed in eastern Texas.
Looking ahead: The NWS WPC 7-Day Quantitative Precipitation Forecast (QPF) calls for moderate-to-heavy liquid accumulations ranging from 2 to 4+ inches across the mid-South and lower Midwest while portions of the Plains, Northeast, Mid-Atlantic, and the Southeast are expected to receive <1-inch accumulations. In the Intermountain West and Pacific Northwest, light precipitation (<1-inch accumulations) is forecasted for areas of the central and northern Rockies, and portions of the Cascades. The CPC 6-10-day Outlook calls for a moderate-to-high probability of above-normal temperatures in the Far West, Southwest, Great Basin, and Florida while a high probability of below-normal temperatures is forecasted across most of the Eastern Tier. In terms of precipitation, there is a moderate probability of above-normal precipitation across areas of the central and southern Plains, as well as the southeastern tier of the U.S. Below-normal precipitation is expected across the Pacific Northwest, Great Plains, and areas of the Intermountain West.