According to the National Drought Monitor, 53.47% of the contiguous U.S. is impacted by some form of drought, which is down from 54.11% last week and down from 65.67% a year ago. The monitor this week focused heavily on parched California and the recent storm that moved into the state. It reports, the "most significant storm of the season" crossed California, delivering drought-easing rainfall to coastal areas and beneficial snow in the Sierra Nevada. In addition, rain in California’s agricultural regions temporarily eased irrigation requirements and aided drought-stressed rangeland and winter grains. However, spring and summer runoff prospects improved only slightly, as pre-storm snowpack values were near record lows and because drought-parched soils soaked up most of the available moisture, it says. In addition, it continues, the storm moved too far south to provide optimal amounts of moisture in California’s key watershed areas, with the heaviest precipitation occurring in coastal and southern California rather than the Sierra Nevada.
The remainder of the West also experienced stormy weather, it reports, with some of the heaviest precipitation occurring in central Arizona. Meanwhile, water-supply prospects further improved under a generally wet regime across the northern tier of the West. East of the Rockies, heavy rain was mostly confined to the Gulf Coast region. In early March, the monitor reports, a late-winter storm unfolded across parts of the Plains, Midwest, mid-South, and mid-Atlantic States, where varying amounts of snow and sleet fell in advance of a record-setting March cold outbreak. By the morning of March 3, more than half (57%) of the contiguous U.S. was covered by snow, according to NOAA’s National Operational Hydrologic Remote Sensing Center.
Central and Southern Plains: The monitor says generally light, wintry precipitation prevented further drought expansion on the central Plains. On March 2, topsoil moisture was rated 87% very short to short in Oklahoma, along with 57% in Nebraska and 55% in Kansas. Rangeland and pastures were rated 46% very poor to poor in Oklahoma, reflective of both short- and long-term drought. In Texas, there were a variety of changes to the drought depiction, both improvement and deterioration, the monitor says. Recent precipitation was heaviest across southern and eastern Texas, where there were widespread changes for the better. General, slight deterioration was noted—with a few exceptions—across northern and western Texas. On March 2, statewide topsoil moisture was rated 78% very short to short in Texas, with numbers topping 90% in several northern and western districts, the monitor reports.
Corn Belt and Mississippi Valley: Rain, sleet, and snow in early March mostly arrested the expansion of abnormal dryness (D0) across the lower half of the Mississippi Valley, the monitor says. During the 7-day drought-monitoring period, precipitation totaled 0.23 inch in Joplin, Missouri, and 0.55 inch in Shreveport, Louisiana. Despite the moisture, year-to-date (January 1 – March 4) precipitation totaled 1.06 inch (22% of normal) in Joplin and 3.85 inches (40%) in Shreveport, Louisiana. Farther north, mostly dry, extremely cold weather covered the Midwestern areas of lingering dryness (D0) and moderate to severe drought (D1 to D2), resulting in no changes to the depiction. Minneapolis-St. Paul, Minnesota reported its 50th day with a below 0°F reading on March 3, the most in any winter at that location since 1977-78, the monitor observes.
Southeast: Additional rain near the Gulf Coast led to the removal of abnormal dryness (D0) from western Florida and a reduction in coverage in southern Alabama. At the same time, year-to-date rainfall deficits led to the introduction of some D0 in east-central Alabama. Anniston, Alabama, near the edge of the new dry area, reported precipitation of 7.49 inches (73% of normal) from January 1 – March 4, the monitor states.
Looking Ahead: From March 6 - 10, a barrage of Pacific moisture will maintain mild, wet conditions in the Northwest, leading to possible flooding as far east as the northern Rockies. Five-day precipitation totals could reach 4 to 8 inches in the Pacific Northwest and 2 to 4 inches in the northern Rockies—although lighter amounts will occur in rain-shadow areas east of the Cascades, the monitor notes. Although some precipitation will graze northern California, central and southern portions of the state will experience warm, mostly dry weather. Meanwhile, a series of disturbances will result in showers across the Deep South, where 5-day rainfall could reach 1 to 3 inches. On March 7, some snow or freezing rain may occur east of the southern Appalachians, as moisture interacts with lingering cold air. Elsewhere, cold weather will linger for several more days across the eastern half of the U.S., although a marked warming trend can be expected early next week, the monitor says.