Click here to visit the US Drought Monitor website. Here’s an excerpt:
Summary
A large upper-level ridge of high pressure spanned the Lower 48 States (CONUS) this USDM week, bringing warmer-than-normal temperatures to most of the CONUS. But Pacific low pressure systems undercut the ridge, dumping rain and snow over many areas. This USDM week (April 19-25) ended up with above-normal precipitation across parts of the west coast, intermountain basin, and northern Rockies; much of the Plains; and parts of the coastal Carolinas. The week was drier than normal across parts of the Pacific Northwest and central Plains, and much of the Southwest, Midwest, and eastern U.S. east of the Mississippi River. Heavy precipitation in the Plains soaked into parched ground, with U.S. Department of Agriculture (USDA) reports of topsoil moisture improving 20 to 40 percent over the last two weeks from Texas to Montana. But continued dry weather in the east further dried soils, resulting in 20 to 40 percent increases in topsoil rated short or very short of moisture from South Carolina to Vermont. Consequently, drought and abnormal dryness contracted across parts of the Plains but expanded in the East. As this USDM week ended Tuesday morning, additional storm systems were poised to move across the CONUS…
The Plains and Mississippi Valley
Heavy precipitation fell on parts of the Plains and upper Mississippi Valley, bringing additional relief to areas where dryness and drought quickly developed over the past several weeks. Over four inches of precipitation was recorded at stations along the Iowa-Nebraska state line, with 2-4 inch reports common in the drought and abnormally dry areas of southeast Nebraska and northeast Kansas. Two or more inches fell over the D0-D1 areas of the Dakotas and Minnesota. The heaviest rains in Texas fell outside the drought and abnormally dry areas, although 1-3 inches was reported at stations in and near the Panhandle drought and abnormally dry areas. D0 was trimmed in Nebraska and D0-D1 were pulled back in Kansas. In the Dakotas and Minnesota, D1 was eliminated and D0 reduced. Parts of south central Minnesota had been drying out over the last several weeks, but 1-3 inches of precipitation this week prevented any expansion of D0 there. D0-D2 were cut back in the Texas panhandle and D0 trimmed in the Trans Pecos region. In the Texas panhandle, Lake Meredith has recovered to levels not seen in the last ten years, although the level is still below those last seen in the 1990s. Continued dry weather from Arkansas to Illinois resulted in expansion of D0 in Missouri and western Illinois. D1 was added in southwest Missouri where 67% of the topsoil moisture and 58% of the subsoil moisture was short or very short, according to April 25 USDA reports…
The Rockies and Intermountain West
Parts of the Great Basin to central Rockies received 1-3 inches of precipitation, with amounts locally over 3 inches in Nevada and adjoining Idaho. Smaller amounts fell to the north, with no precipitation reported across much of the Southwest. D0 was pulled back in parts of Montana and Wyoming, and D2 in south central Montana was deleted. D0 expanded in central Montana and across southeastern Utah where precipitation was below normal this week and deficits have intensified over the last 30-120 days…
The Far West
Coastal Washington and Oregon received 1-3 inches of precipitation this week, but these areas were outside the drought and abnormally dry region. Precipitation amounts were much lighter east of the Cascades, generally less than half an inch. In northern California, 1-3 inches of precipitation fell along the northern Sierra, which translates to well above normal, but normals are lower this time of year and the amounts are small compared to the multi-year deficits, so no change was made to the depiction in California and Nevada…
Looking Ahead
In the two days since the issuance of the April 26 USDM, additional heavy rain has fallen across the drought and abnormally dry areas of the central Plains, and precipitation of varying amounts has occurred over the drought and abnormally dry areas of other parts of the CONUS. During April 28-May 2, a large upper-level weather system and associated frontal systems are forecast to bring moderate precipitation totals of 0.5 to 2.0 inches, with locally higher amounts, to parts of the intermountain basin to central and northern Rockies, much of the Great Plains to Mississippi and Ohio Valleys, and the mid-Atlantic to Southeast. Less than half an inch is predicted for the Far West, southern portions of the Southwest, northern Great Lakes, New England, and central to southern Florida. The upper-level low is expected to keep temperatures below average for much of the country, with above-normal temperatures limited to the Far West and Southeast to southern Plains.
The odds favor above-normal precipitation across the Southwest, Gulf of Mexico and Atlantic coasts, and most of Alaska during May 3-7, 2016. There are enhanced chances for subnormal precipitation across the Pacific Northwest to western Great Lakes, much of the CONUS from the Rockies to Appalachians, and extreme northwest Alaska. Enhanced chances for colder-than-normal conditions exist for the southern Plains to New England, while warmer-than-normal weather is favored across the West to northern Plains, Alaska, and southern Florida.