#Drought news: #Snow blankets the #West, major improvements in Four Corners and W. #Colorado

Click on a thumbnail graphic to view a gallery of drought data from the US Drought Monitor.

Click here to go the US Drought Monitor website. Here’s an excerpt:

Summary

A pair of late-winter storms blanketed large areas of the West with snow, easing drought; bolstering high-elevation snowpack; and further improving spring and summer runoff prospects. The first storm system, which swept across the Southwest from February 20-22, produced heavy precipitation in core drought areas of the Four Corners States and deposited measurable snow in locations such as Las Vegas, Nevada, and Tucson, Arizona. The second storm—in actuality a series of disturbances—began to affect parts of the Northwest during the weekend of February 23-24 and later delivered another round of heavy precipitation across northern California. Farther east, drenching rain resulted in aggravated and expanded flooding from the northern Mississippi Delta into the southern Appalachians. Rainfall totaled 4 to 12 inches or more in the flood-affected area, with some of the highest amounts occurring in the Tennessee Valley. On February 23-24, thunderstorms spawned several tornadoes in Alabama, Georgia, and Mississippi. Farther north, a blizzard briefly engulfed portions of the northern and central Plains and upper Midwest. The short-lived but fierce storm produced several inches of snow, driven by wind gusts in excess of 60 mph, mainly on February 23-24. High winds also raked the southern Plains—without the benefit of significant precipitation—compounding the effects of short-term dryness on winter wheat and rangeland health…

High Plains

Abnormal dryness (D0) was also removed from North Dakota, following a protracted period of below-normal temperatures and frequent snowfall events. The drought situation for Wyoming and Colorado will be covered in the section devoted to the West…

West

As described in the summary section, major storm systems affected core drought areas in Oregon and the Four Corners region, respectively, leading to locally significant reductions in the coverage of dryness (D0) and moderate to exceptional drought (D1 to D4). By late February, nearly all Western river basins, except a few in southern New Mexico, are experiencing near- to above-average snowpack. In addition, the recent spate of cold weather has maximized snow accumulations, even at middle and lower elevations. According to the California Department of Water Resources, the average water content of the Sierra Nevada snowpack by February 26 stood at 36 inches—150% of average for the date and approximately 130% of average peak value. In Oregon, extreme drought (D3) was eradicated, while substantial reductions were realized in the coverage of moderate to severe drought (D1 to D2). Drought was nearly pushed out of California, with only a lingering sliver of moderate drought (D1) along the Oregon border. Major improvements were also introduced in parts of Nevada, Idaho, Utah, Colorado, and Arizona. Extreme drought (D3) was nearly eased out of southern Colorado, leaving a remnant area of extreme to exceptional drought (D3 to D4) across northern New Mexico. In another example of a major reduction, the former large Western area of moderate drought (D1) was split into three pieces, with cuts across Nevada/Idaho, and Utah/Wyoming/Colorado, respectively…

South

Some of the heavy rain that fell across the mid-South grazed the central Gulf Coast region, resulting in a slight reduction in the coverage of abnormal dryness (D0). Farther west, abnormal dryness (D0) and moderate drought (D1) was broadly expanded across western and southern Texas, as well as southwestern Oklahoma. According to the U.S. Department of Agriculture, 21% of the winter wheat in Texas was in very poor to poor condition on February 24. On the same date, 28% of Texas’ rangeland and pastures were categorized as very poor to poor, while statewide topsoil moisture was 42% very short to short. Topsoils were especially dry (moisture was 86% very short to short) on Texas’ southern high plains and in the lower Rio Grande Valley (79% very short to short). From December 1, 2018 – February 26, 2019, rainfall in McAllen, Texas, totaled just 1.81 inches (55% of normal). Elsewhere in Texas, year-to-date precipitation through February 19 totaled less than one-quarter of an inch in Childress (0.19 inch, or 11% of normal), Dalhart (0.08 inch, or 9%), and Lubbock (0.04 inch, or 3%)…

Looking Ahead

The storm system currently affecting the West will lose some organization while traversing the central and eastern U.S. Nevertheless, 5-day rainfall totals could reach 1 to 3 inches or more in the Southeast, while periods of generally light snow will affect portions of the Plains, Midwest, and Northeast. During the weekend and early next week, a strong surge of cold air will engulf the Plains and Midwest, with sub-zero temperatures expected as far south as northern sections of Kansas and Missouri. In addition, sub-freezing temperatures could reach into the Deep South. Farther west, a new storm system should arrive in California during the weekend, with wintry precipitation rapidly spreading eastward across portions of the southern U.S. by early next week. Outside of the contiguous U.S., Alaska’s drought areas will continue to experience cold, mostly dry weather during the next few days, while locally heavy showers over Hawaii’s Big Island will shift east of the state by late in the week. Elsewhere, conditions over Puerto Rico will favor a slight increase in shower activity, although no widespread, organized rainfall is expected into early next week.

The NWS 6- to 10-day outlook for March 5 – 9 calls for the likelihood of colder-than-normal conditions nationwide, except for near-normal temperatures in southern Florida and above-normal temperatures in parts of the Southwest. Meanwhile, wetter-than-normal weather from California into the middle Mississippi Valley should contrast with below-normal precipitation in the upper Great Lakes region and most areas east of the Mississippi River.

West Drought Monitor one week change map ending February, 26, 2019.

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