This Week's Drought Summary (4/9)

April 9, 2020


This U.S. Drought Monitor week saw drought expansion across portions of the South (Louisiana, Mississippi) and Southeast (Florida) where warm and dry conditions prevailed during the past 90-day period causing declines in soil moisture and streamflow levels. In Texas, significant rainfall across parts of the state led to improvement in drought-related conditions in South Texas and the Hill Country while areas along the Texas Gulf Coast missed the heavier accumulations. In the northern Plains, record-breaking cold affected the region including eastern portions of Wyoming and Montana. Further West, another series of Pacific storms delivered beneficial rainfall to coastal areas and valley locations in California and Oregon while significant mountain snowfall was observed across the Sierra Nevada, Trinity Mountains of northern California, Cascades, and the northern Rockies. For the month of March, the contiguous U.S. experienced its 30th wettest on record as well as its 10th warmest including record-warmth observed in areas of Texas, Louisiana, Mississippi, Alabama, Georgia, and Florida.


On this week’s map, the region remained drought free. During the 7-day period, a Nor’easter impacted parts of the region bringing damaging winds, rain and snow, and some minor coastal flooding with the heaviest precipitation accumulations for the week (1.0-to-2.5 inches liquid) observed in eastern Massachusetts, New Hampshire, and Maine. Average temperatures for the week were above normal (2-to-5º F) across most of the region with the exception of coastal areas of Massachusetts and Rhode Island that saw average temperatures that were 1-to-3 degrees below normal. According to the National Weather Service (NWS) National Operational Hydrologic Remote Sensing Center (NOHRSC), 29.6% of the region was covered by snow (compared to 71.3% last month) with an average depth of 4.4 inches and a maximum depth of 88.9 inches. According to the National Centers for Environmental Information (NCEI), the Northeast Climate Region experienced its 10th warmest and 67th wettest March on record.


During the past week, most of the region was dry with some light precipitation observed (generally <1 inch) in isolated areas of southern portions of Alabama and Georgia as well as in parts of Florida. A combination of indicators—including above normal temperatures, lack of rainfall, declining soil moisture, and low streamflow levels—led to continued expansion of areas of Moderate Drought (D1) and Severe Drought (D2) in northern Florida as well as expansion of areas of Abnormally Dry (D0) in central and southern Alabama plus southern Georgia. Elsewhere in the region, some lesser rainfall accumulations (generally <1 inch) were observed along coastal areas of North Carolina as well as in southern Virginia. According to NCEI, the Southeast Climate Region experienced its 4th warmest March on record with Florida seeing its warmest and 2nd driest March on record while Alabama, Georgia, and South Carolina had their 5th warmest March on record. According to the USDA (April 5), the percentage of topsoil moisture rated short to very short was as follows: Alabama 16%, Florida 64%, Georgia 26%, South Carolina 2%, North Carolina 5%, and Virginia 9%.


On this week’s map, drought-affected areas of Texas saw widespread improvements in areas of Moderate (D1), Severe Drought (D2), Extreme Drought (D3), and Exceptional Drought (D4) in response to moderate-to-heavy to rainfall accumulations (ranging from 2-to-5 inches) in South Texas as well as in the Hill Country during the past 7-day period. Drought-stricken areas along much of the Gulf Coast of Texas, however, received accumulations of generally less than one inch. According to the USDA, topsoil moisture in Texas was rated 27% short to very short while Louisiana rated 18% short to very short. In Louisiana and Mississippi, areas of Abnormally Dry (D0) and Moderate Drought (D1) expanded along southern portions in response to another week of warm and dry conditions with numerous streamflow gaging stations reporting 7-day average streamflow levels below the 25th percentile. In the Oklahoma Panhandle, dry conditions persisted this week leading to minor expansion of areas with Abnormally Dry (D0), Moderate Drought (D1), and Severe Drought (D2) ratings. As a region, the South Climate Region experienced its 13th wettest March and 5th warmest.


On this week’s map, the region remained drought free. For the week, some wintery weather impacted part of Minnesota with snowfall accumulations ranging from 6-to-16 inches in areas of northwestern Minnesota, increasing the likelihood of major springtime flooding in the Red River Valley. According to the NWS NOHRSC, 20.6% (as compared to 58.9% last month) of the Northern Great Lakes Region is covered by snow while the Upper Midwest region is 3.2% covered by snow (compared to 33.7%) last month. According to NCEI, the Ohio Valley Climate Region had it 15th wettest (13th warmest) March on record while the Upper Midwest Climate Region experienced its 23rd wettest (15th warmest).

High Plains